Aa Mutations Research Articles

Downstream Link of Vitamin D Pathway with Inflammation Irrespective of Plasma 25OHD3: Hints from Vitamin D-Binding Protein (DBP) and Receptor (VDR) Gene Polymorphisms

Background: Vitamin D insufficiency/deficiency is a highly prevalent condition worldwide. At the same time, chronic inflammation is a versatile pathophysiological feature and a common correlate of various disorders, including vitamin D deficiency. Methods: We investigated the possible association of inflammation with 25-hydroxyvitamin D3 (25OHD3) levels and its down-stream pathway by exploring vitamin D-binding protein (DBP) and vitamin D receptor (VDR) genes for single-nucleotide polymorphisms (SNPs), in healthy non-elderly Bahraini adults. Plasma levels of 25OHD3 were measured by chemiluminescence, and six SNPs, four in the GC gene (rs2282679AC, rs4588CA, rs7041GT, and rs2298849TC) and two in the VDR gene (rs731236TC and rs12721377AG) were genotyped by real-time PCR. The concentrations of five inflammatory biomarkers, IL6, IL8, procalcitonin (PCT), TREM1, and uPAR, were measured by ELISA. Results: The results showed no association between the 25OHD3 level and any of the inflammatory markers’ levels. However, three tested SNPs were significantly associated with the concentrations of tested biomarkers except for IL6. The TT mutant genotype of rs2298849TC was associated with lower levels of IL8 and higher levels of PCT and TREM1, the AA mutant genotype of rs2282679AC was associated with decreased levels of IL8 (p ≤ 0.001) and increased levels of TREM1 (p = 0.005), and the GG wild genotype of rs12721377AG was associated with increased levels of 25OHD3 (p = 0.026). Conclusions: Although chronic inflammation is not associated with the vitamin D system in the blood, it is downstream, as revealed by DBP and VDR genotyping. Alternatively, DBP and VDR pursue other functions beyond the vitamin D pathway.

Significance Of Gene Polymorphisms In Joint Destruction In Reactive Arthritis

in patients with reactive arthritis (ReA), cytokines produced by Th17 cells, one of them IL17, affect cell differentiation, recruitment, activation of immune cells, and release of antimicrobial peptides. Among the cytokines of the IL-17 family, it is IL-17A that is of decisive importance in the induction of pathological bone resorption through direct activation of osteoclast precursors during the formation of the articular syndrome The aim of our work was to study the distribution of allele and genotype frequencies of the polymorphic region G197A (rs2275913) of the IL-17A gene in patients with ReA. As a result of the study, there were no significant differences in the distribution of alleles of the G197A polymorphism of the IL-17A gene in patients with ReA and apparently healthy people. But when comparing genotypic variants, we revealed differences: healthy GG and mutant AA genotypes were more common in patients, while the heterozygous GA genotype was more common in healthy people

Abstract 4134837: Checkpoint Kinase 1 Attenuates Myocardial Ischemia-Reperfusion Injury Through Maintaining SIRT1-Dependent Mitochondrial Homeostasis

Background: Mitochondrial dysfunction is linked to myocardial ischemia-reperfusion (I/R) injury. Checkpoint kinase 1 (CHK1) could facilitate cardiomyocyte proliferation and cardiac repair post myocardial infarction, however, its role on mitochondrial function in I/R injury remains unknown. Research Questions: The purpose of this study is to explore the potential effects and mechanisms of CHK1 on mitochondrial homeostasis during myocardial I/R injury. Methods: To investigate the role of CHK1 on mitochondrial function following I/R injury, cardiomyocyte-specific knockout/knock-in mouse models were generated. Mass spectrometry-proteomics analysis and protein co-immunoprecipitation assays were conducted to dissect the molecular mechanism of CHK1. The interaction between CHK1 and SIRT1 was explored using truncated plasmids. Results: CHK1 was downregulated in myocardium post I/R and neonatal mouse cardiomyocytes (NMCMs) post oxygen-glucose deprivation/re-oxygenation (OGD/R). In vivo , CHK1 overexpression protected against myocardial I/R injury, while heterogenous CHK1 knockout exacerbated cardiomyopathy. In vitro , CHK1 inhibited OGD/R-induced cardiomyocyte apoptosis and bolstered cardiomyocyte survival. Mechanistically, CHK1 attenuated oxidative stress and preserved mitochondrial metabolism in cardiomyocytes under I/R. Moreover, disrupted mitochondrial homeostasis in I/R myocardium was restored by CHK1 through the promotion of mitochondrial biogenesis and mitophagy. Through mass spectrometry analysis following co-immunoprecipitation, SIRT1 was identified as a direct target of CHK1. The 266-390 domain of CHK1 interacted with the 160-583 domain of SIRT1. Importantly, CHK1 phosphorylated SIRT1 at Thr530 residue, thereby inhibiting SMURF2-mediated degradation of SIRT1. CHK1 Δ390 amino acids (aa) mutant functioned similarly to full-length CHK1 in scavenging ROS and maintaining mitochondrial dynamics. Consistently, cardiac-specific SIRT1 knockdown partially attenuated the protective role of CHK1 in I/R injury. Conclusions: Our findings revealed that CHK1 mitigates I/R injury and restores mitochondrial dynamics in cardiomyocytes through a SIRT1-dependent mechanism.

CHK1 attenuates cardiac dysfunction via suppressing SIRT1-ubiquitination

BackgroundMitochondrial dysfunction is linked to myocardial ischemia-reperfusion (I/R) injury. Checkpoint kinase 1 (CHK1) could facilitate cardiomyocyte proliferation, however, its role on mitochondrial function in I/R injury remains unknown. MethodsTo investigate the role of CHK1 on mitochondrial function following I/R injury, cardiomyocyte-specific knockout/overexpression mouse models were generated. Adult mouse cardiomyocytes (AMCMs) were isolated for in vitro study. Mass spectrometry-proteomics analysis and protein co-immunoprecipitation assays were conducted to dissect the molecular mechanism. ResultsCHK1 was downregulated in myocardium post I/R and AMCMs post oxygen-glucose deprivation/re‑oxygenation (OGD/R). In vivo, CHK1 overexpression protected against I/R induced cardiac dysfunction, while heterogenous CHK1 knockout exacerbated cardiomyopathy. In vitro, CHK1 inhibited OGD/R-induced cardiomyocyte apoptosis and bolstered cardiomyocyte survival. Mechanistically, CHK1 attenuated oxidative stress and preserved mitochondrial metabolism in cardiomyocytes under I/R. Moreover, disrupted mitochondrial homeostasis in I/R myocardium was restored by CHK1 through the promotion of mitochondrial biogenesis and mitophagy. Through mass spectrometry analysis following co-immunoprecipitation, SIRT1 was identified as a direct target of CHK1. The 266–390 domain of CHK1 interacted with the 160–583 domain of SIRT1. Importantly, CHK1 phosphorylated SIRT1 at Thr530 residue, thereby inhibiting SMURF2-mediated degradation of SIRT1. The role of CHK1 in maintaining mitochondrial dynamics control and myocardial protection is abolished by SIRT1 inhibition, while inactivated mutation of SIRT1 Thr530 fails to reverse the impaired mitochondrial dynamics following CHK1 knockdown. CHK1 Δ390 amino acids (aa) mutant functioned similarly to full-length CHK1 in scavenging ROS and maintaining mitochondrial dynamics. Consistently, cardiac-specific SIRT1 knockdown attenuated the protective role of CHK1 in I/R injury. ConclusionsOur findings revealed that CHK1 mitigates I/R injury and restores mitochondrial dynamics in cardiomyocytes through a SIRT1-dependent mechanism.

Epidemiology and molecular evolution of GI.1 sapovirus in the recent era.

Sapovirus (SaV) infection is increasing worldwide. Herein, we provided evidence of a significant increase in SaV infection in Japan during 2010-2022, primarily due to the considerable (p = 0.0003) rise of the GI.1 genotype. Furthermore, we found that all major and minor SaV outbreaks in Japan, including the largest SaV outbreak in 2021-2022, were caused by the GI.1 genotype. Therefore, to get insight into the underlying molecular mechanism behind this rising trend of the SaV GI.1 type, we selected 15 SaV GI.1 outbreak strains for complete genome analysis through next-generation sequencing. Phylogenetically, our strains remained clustered in different branches in lineages I and II among the GI.1 genotype. We showed all amino acid (aa) substitutions in different open reading frames (ORFs) in these strains. Importantly, we have demonstrated that the strains involved in the largest SaV outbreak in Japan in 2021-2022 belonged to lineage II and possessed the third ORF. We have identified some unique aa mutations in these major outbreak strains in the NS1 and NS6-NS7 regions that are thought to be associated with viral pathogenicity, cell tropism, and epidemiological competence. Thus, in addition to enriching the database of SaV's complete sequences, this study provides insights into its important mutations.

The Value IRS-1 rs1801278G > A Polymorphism Testing in Evaluating Infertile Women with Polycystic Ovarian Syndrome: A Case-control Study

Background: Polycystic ovary syndrome (PCOS) is a leading cause of infertility. Insulin resistance is a key element in pathogenesis. The insulin receptor causes phosphorylation of the insulin receptor substrate (IRS); IRS-1 rs1801278G > A polymorphism variant is the most common genetic variant associated with IR and PCOS. Objective: We aimed to examine the frequency of IRS-1 rs1801278G > A polymorphism variant and test its value in evaluating infertile PCOS women. Methods: A case-control study recruited 140 age and body-mass-matched participants in the university hospital, subdivided according to Rotterdam criteria into PCOS cases (70/140) and healthy controls (70/140). We collected demographic data, ultrasonic [antral follicles and endometrial thickness], hormonal [FSH, LH, AMH, E2], and genetic data by polymerase chain reaction for analysis. Result: Wild GG SNP rs1801278 G was meaningfully higher among controls (58.57%, P<0.0001). Mutant AA SNP rs1801278 was significantly higher in PCOS women (37.14%, P-value =0.0001, an odds ratio of 20.50, 95% CI (9.42-28.63) to develop PCOS. Heterogenous GA gene SNP rs1801278 showed a trend of higher frequency in PCOS patients with 44.29%; OR of 3.91, 95% CI (1.37–7.55); P = 0.422. Upon correlating infertility parameters to SNP rs1801278 G>A polymorphism, statistical differences were found with AFC, LH/FSH ratio, and serum testosterone. As for the AMH, E2, and endometrial thickness, they failed to have a statistical value. Conclusion: The significant correlation of genetic polymorphism to infertility parameters among PCOS women opens a new therapeutic and prognostic avenue that helps gynecologists tailor manganate for a better and safer outcome.

Cervical cancer risk in association with TNF-alpha gene polymorphisms in Bangladeshi women.

Tumor necrosis factor-alpha (TNF-α) is among the vital pro-inflammatory cytokines that potentially exerts a significant influence on the immune response, hence potentially regulating the advancement of cervical lesions. Our study objective was to examine the relationship between two single nucleotide polymorphisms (SNPs) (rs1799724 and rs1800629) of TNF-α and the risk of cervical cancer in women from Bangladesh. We recruited 133 patients with cervical cancer and 126 healthy individuals for this study. Genotyping was performed using real-time PCR SNP genotyping assay. Multivariate logistic regression analysis was used to determine the odds ratio (OR) along with 95% confidence intervals (CI) and p-values. For rs1799724 (C > T) polymorphism, TT mutant homozygous genotype carried 3.26 times increased risk of developing cervical cancer (OR = 3.26, 95% CI = 1.15-9.28, p = 0.027). Polymorphism of rs1800629 (G > A) was also related to an elevated risk of cervical cancer. Individuals with the AG heterozygous genotype (OR = 2.85, 95% CI = 1.20-6.74, p = 0.017) and AA mutant homozygous genotype (OR = 4.55, 95% CI = 1.24-16.60, p = 0.022) also had a higher likelihood of having cervical cancer. Moreover, we found that injectable contraceptives increase the risk of cervical cancer. Individuals who smoked and/or had first-degree relatives with cancer were more likely to carry the risk allele, which increases the likelihood of developing cervical cancer. TNF-α polymorphisms in rs1799724 and rs1800629 increase the susceptibility of developing cervical cancer in women from Bangladesh.

The mutation of Japanese encephalitis virus envelope protein residue 389 attenuates viral neuroinvasiveness

The envelope (E) protein of the Japanese encephalitis virus (JEV) is a key protein for virus infection and adsorption of host cells, which determines the virulence of the virus and regulates the intensity of inflammatory response. The mutation of multiple aa residues in the E protein plays a critical role in the attenuated strain of JEV. This study demonstrated that the Asp to Gly, Ser, and His mutation of the E389 site, respectively, the replication ability of the viruses in cells was significantly reduced, and the viral neuroinvasiveness was attenuated to different degrees. Among them, the mutation at E389 site enhanced the E protein flexibility contributed to the attenuation of neuroinvasiveness. In contrast, less flexibility of E protein enhanced the neuroinvasiveness of the strain. Our results indicate that the mechanism of attenuation of E389 aa mutation attenuates neuroinvasiveness is related to increased flexibility of the E protein. In addition, the increased flexibility of E protein enhanced the viral sensitivity to heparin inhibition in vitro, which may lead to a decrease in the viral load entering brain. These results suggest that E389 residue is a potential site affecting JEV virulence, and the flexibility of the E protein of aa at this site plays an important role in the determination of neuroinvasiveness.

CYP1A2 Polymorphism and Drug Co-administration Affect the Blood Levels and Adverse Effects of Pirfenidone.

Mutations in metabolic enzymes and co-administration of drugs may affect the blood concentration of pirfenidone effective in pulmonary fibrosis. To provide a basis for the precise clinical use of pirfenidone, the authors analyzed the correlation between steady-state pirfenidone trough concentration and adverse drug reactions (ADRs) and examined the impact of CYP1A2*1C (rs2069514) and *1F (rs762551) variants and co-administration on pirfenidone blood concentrations and ADRs. Forty-four patients were enrolled. The blood concentration of pirfenidone was determined using high-performance liquid chromatography. CYP1A2*1C and *1F genotypes were determined using direct SNP sequencing. Additional information related to drug associations was collected to screen factors affecting drug metabolism. The highest predictive value of ADRs was observed when the steady-state trough concentration of pirfenidone was 3.18 mcg·mL-1 and the area under the receiver operating characteristic curve was 0.701 (P = 0.024). The pirfenidone concentration-to-dose ratio (C/D) in CYP1A2*1F homozygous AA mutants was lower than that in C carriers (CC+AC) (1.28 ± 0.85 vs. 2.03 ± 1.28 mcg·mL-1; P = 0.036). Adverse drug reaction (ADR) incidence in the homozygous AA mutant group (28.0%) was significantly lower than that in the C carriers (CC+AC) (63.2%; P = 0.020), and ADR incidence in the A carriers (AC+AA) was considerably lower than that in the CC group (85.7%; P = 0.039). The C/D value of the combined lansoprazole/rabeprazole group was lower than that of the noncombination group (P < 0.05). The ADR incidence was positively correlated with pirfenidone blood concentration. The CYP1A2 (rs762551) AA genotype is associated with lower pirfenidone concentrations and fewer ADRs. Lansoprazole/rabeprazole co-administration reduced pirfenidone concentrations. Randomized controlled trials should further explore personalized dosing of pirfenidone and combination therapies.

Correlation between Metabolic Parameters and Warfarin Dose in Patients with Heart Valve Replacement of Different Genotypes.

Warfarin has become the first choice for anticoagulation in patients who need lifelong anticoagulation due to its clinical efficacy and low price. However, the anticoagulant effect of warfarin is affected by many drugs, foods, etc. accompanied by a high risk of bleeding and embolism. The Vitamin K epoxide reductase complex 1 (VKORC1) and Cytochrome P450 2C9 (CYP2C9) genotypic variation can influence the therapeutic dose of warfarin. However, it is not clear whether there is a correlation between warfarin dose and liver function, kidney function and metabolic markers such as uric acid (UA) in patients with different genotypes. We performed a single-center retrospective cohort study to evaluate the factors affecting warfarin dose and to establish a dose conversion model for warfarin patients undergoing heart valve replacement. We studied 343 patients with a mechanical heart valve replacement, compared the doses of warfarin in patients with different warfarin-related genotypes (CYP2C9 and VKORC1), and analyzed the correlation between liver function, kidney function, UA and other metabolic markers and warfarin dose in patients with different genotypes following heart valve replacement. Genotype analysis showed that 72.01% of patients had CYP2C9*1/*1 and VKORC1 mutant AA genotypes. Univariate regression analysis revealed that the warfarin maintenance dose was significantly correlated with gender, age, body surface area (BSA), UA and genotype. There was no correlation with liver or kidney function. Multiple linear regression analysis showed that BSA, genotype and UA were the independent factors influencing warfarin dose. There is a significant correlation between UA content and warfarin dose in patients with heart valve replacement genotypes CYP2C9*1/*1/VKORC1(GA+GG), CYP2C9*1/*1/VKORC1AA and CYP2C9*1/*1/VKORC1AA.

Genomic characterization and pathogenicity of a novel fowl adenovirus serotype 11 isolated from chickens with inclusion body hepatitis in China

Fowl adenovirus serotype 11 (FAdV-11) is one of the primary causative agents of inclusion body hepatitis (IBH), which causes substantial economic losses in the world poultry industry. In this study, we characterized the genome of the fowl adenovirus serotype 11 (FAdV-11) isolate FJSW/2021. The full genome of FJSW/2021 was 44, 154 base pairs (bp) in length and had a similar organization to that of previously reported FAdV-11 isolates. Notably, compared with those of other reported FAdV-11 strains, the preterminal protein (pTP) of FAdV-11 FJSW/2021 has six amino acid (aa) insertions (S-L-R-I-I-C) between 470 and 475 and one aa mutation of L476F; moreover, the tandem repeat (TR) regions of TR1 and TR2 were 33 bp (1 repeat) and 1,080 bp (8 repeats) shorter than those of the Canadian nonpathogenic isolate ON NP2, respectively. The pathogenicity of FJSW/2021 was studied in 10-day-old specific pathogen-free chicken embryos following allantoic cavity inoculation and in 1-day-old, 1-wk-old and 2-wk-old SPF chickens following intramuscular inoculation with 107 TCID50 of the virus. The results showed that FJSW/2021 can induce typical severe IBH in chicks less than 2 wk old. These findings highlighted the genetic differences between the pathogenic and non-pathogenic FAdV-11 isolates. The data will provide guidance for identifying the virulence factors of FAdV-11 strains. The animal challenge model developed in our study will allow precise evaluation of the efficacy of potential FAdV-11 vaccine candidates.

Identification and Genome Characterization of a Novel Muscovy Duck-Origin Goose Parvovirus with Three Recombinant Regions between Muscovy Duck Parvovirus and Goose Parvovirus

Muscovy duck-origin goose parvovirus (MDGPV) is a new virus resulting from the natural recombination of Muscovy duck parvovirus (MDPV) and goose parvovirus (GPV). Previously identified MDGPV strains were found to have two recombination regions, one in the P9 promoter to the NS region and one in the VP3 gene, or only one recombination in the VP3 gene. In 2022, a novel strain of MDGPV known as 2022FZ was identified from China’s mainland. Complete genome sequence analysis showed that there were three recombination regions in this strain: one located in the P9 promoter-NS (425–612 nt) region, one in the NS2 (1,483–1,824 nt) region, and one in the VP3 (3,124–4,248 nt) region, respectively. The recombination regions in the P9 promoter-NS, NS2, and VP3 genes were substituted with the relevant GPVs sequences, whereas the MDPV virulent strain served as the skeleton in this instance. In addition, the 2022FZ strain had multiple unique aa mutations in the NS protein and the VP protein. The Muscovy duckling challenge test showed that MDGPV-2022FZ is less pathogenic to Muscovy ducklings than two recombinant or sole recombinant MDGPV strains. For the first time, our study identified a three-region recombinant MDGPV strain and detected the novel recombination event in the NS2 gene. These results contribute to our understanding of the pathogenicity and genetic diversity of duck parvovirus.

Association between Single Nucleotide Polymorphisms of PRKD1 and KCNQ3 Gene and Milk Quality Traits in Gannan Yak (Bos grunniens).

Protein kinase D1 (PRKD1) functions primarily in normal mammary cells, and the potassium voltage-gated channel subfamily Q member 3 (KCNQ3) gene plays an important role in controlling membrane potential and neuronal excitability, it has been found that this particular gene is linked to the percentage of milk fat in dairy cows. The purpose of this study was to investigate the relationship between nucleotide polymorphisms (SNPs) of PRKD1 and KCNQ3 genes and the milk quality of Gannan yak and to find molecular marker sites that may be used for milk quality breeding of Gannan yak. Three new SNPs were detected in the PRKD1 (g.283,619T>C, g.283,659C>A) and KCNQ3 gene (g.133,741T>C) of 172 Gannan lactating female yaks by Illumina yak cGPS 7K liquid-phase microarray technology. Milk composition was analyzed using a MilkoScanTM milk composition analyzer. We found that the mutations of these three loci significantly improved the lactose, milk fat, casein, protein, non-fat milk solid (SNF) content and acidity of Gannan yaks. The lactose content of the TC heterozygous genotype population at g.283,619T>C locus was significantly higher than that of the TT wild-type population (p < 0.05); the milk fat content of the CA heterozygous genotype population at g.283,659C>A locus was significantly higher than that of the CC wild-type and AA mutant populations (p < 0.05); the casein, protein and acidity of the CC mutant and TC heterozygous groups at the g.133,741T>C locus were significantly higher than those of the wild type (p < 0.05), and the SNF of the TC heterozygous group was significantly higher than that of the mutant group (p < 0.05). The results showed that PRKD1 and KCNQ3 genes could be used as candidate genes affecting the milk traits of Gannan yak.

Abstract B006: Mutant PPP2R1A induces the expression and secretion of IGFBP2 to promote uterine serous carcinoma metastasis

Abstract Uterine serous carcinoma (USC) tumors demonstrate a unique aggressiveness suggesting that the primary tumor is intrinsically equipped to disseminate, metastasize and initiate tumor formation at secondary sites. Yet the drivers and pathways regulating dissemination and metastasis in USC remain incompletely understood. Previous work by our group and others identified a mutational hotspot within PPP2R1A, which encodes the Aa scaffolding subunit of protein phosphatase 2A (PP2A), a heterotrimeric serine/threonine phosphatase and known tumor suppressor. Two recurrent mutations, P179R and S256F, occur exclusively within high-grade subtypes of uterine cancer at a rate of 30-40%. We previously published that the P179R mutant drives USC tumorigenesis through the inactivation of PP2A, and genetic correction of this mutant resulted in decreased primary and metastatic tumor formation. The underlying mechanisms for these observations, however, remain unclear. To study the mechanistic basis for these observations, we generated isogenic patient-derived USC cell lines expressing the Aa – P179R and S256F mutants. Expression of these mutants enhanced the tumor-initiating capacity (TIC), a hybrid epithelial to mesenchymal (EM) plasticity profile, and the secretion of tumor-promoting factors in vitro and in vivo. Molecular analysis of these cell lines and tumors demonstrated that these mutants drove increased NF-kb phosphorylation resulting in the upregulation and secretion of the EM cytokine, IGFBP2. We found that the Aa mutant phenotype was dependent on the IGFBP2 cytokine function in vitro and in vivo. Future experiments will focus on identifying which PP2A B regulatory subunits are responsible for regulating the onset of the NF-kb transcriptional program. Cellular reprogramming through the IGFBP2-induced NF-kb signaling pathway mediated by recurrent Aa mutants may explain the intrinsically aggressive nature of USC, through enhanced dissemination and metastasis. Citation Format: Terrance James Haanen, Sophie Boock, Sarah Taylor, Caitlin O'Connor, Analisa DiFeo, Goutham Narla. Mutant PPP2R1A induces the expression and secretion of IGFBP2 to promote uterine serous carcinoma metastasis [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr B006.

PLK1 phosphorylates RhoGDI1 and promotes cancer cell migration and invasion

BackgroundRho guanine nucleotide dissociation inhibitor 1 (RhoGDI1) plays an important role in diverse cellular processes by regulating Rho guanosine triphosphate (GTP)ases activity. RhoGDI1 phosphorylation regulates the spatiotemporal activation of Rho GTPases during cell migration. In this study, we identified polo-like kinase 1 (PLK1) as a novel kinase of RhoGDI1 and investigated the molecular mechanism by which the interaction between RhoGDI1 and PLK1 regulates cancer cell migration.MethodsImmunoprecipitation, GST pull-down assay, and proximity ligation assay (PLA) were performed to analyze the interaction between RhoGDI1 and PLK1. In vitro kinase assay and immunoprecipitation were performed with Phospho-(Ser/Thr) antibody. We evaluated RhoA activation using RhoGTPases activity assay. Cell migration and invasion were analyzed by transwell assays.ResultsGST pull-down assays and PLA showed that PLK1 directly interacted with RhoGDI1 in vitro and in vivo. Truncation mutagenesis revealed that aa 90-111 of RhoGDI1 are critical for interacting with PLK1. We also showed that PLK1 phosphorylated RhoGDI1 at Thr7 and Thr91, which induces cell motility. Overexpression of the GFP-tagged RhoGDI1 truncated mutant (aa 90-111) inhibited the interaction of PLK1 with RhoGDI1 and attenuated RhoA activation by PLK1. Furthermore, the overexpression of the RhoGDI1 truncated mutant reduced cancer cell migration and invasion in vitro and suppressed lung metastasis in vivo.ConclusionsCollectively, we demonstrate that the phosphorylation of RhoGDI1 by PLK1 promotes cancer cell migration and invasion through RhoA activation. This study connects the interaction between PLK1 and RhoGDI1 to the promotion of cancer cell behavior associated with malignant progression, thereby providing opportunities for cancer therapeutic interventions.

Abstract B071: A genetic approach to selectively inhibit macropinocytosis while sparing autophagy

Abstract Macropinocytosis is a bulk endocytic process that can fuel tumor growth and drug resistance by providing access to extracellular protein and necrotic cell debris. This process is primarily studied by utilizing the chemical inhibitor, 5-(N-ethyl-N-isopropyl)-Amiloride (EIPA), but this inhibitor is nonselective can hinder proliferation even in non-macropinocytic breast cancer cells. Hence, a more selective, genetic approach is needed. Formation of macropinosomes is dependent on the actin cytoskeleton, which in turn is regulated by CARMIL1, a large multimeric protein that regulates the actin capping protein. CARMIL1 is essential for macropinocytosis, and mutation of two residues in the Capping-Protein Interaction (CPI) region of CARMIL1 to alanine (CARMIL1-AA) limits the CARMIL1-capping protein interaction and more importantly, inhibits macropinocytosis upon introduction of exogenous CARMIL1-AA in tumor cells. Therefore, CARMIL1-AA is a genetic tool to study the effects of macropinocytosis on other cellular processes. However, autophagy, a lysosome-dependent recycling system that enables cell survival, additionally utilizes actin to form autophagosomes. The overall goal of this project is to determine whether CARMIL1-AA specifically inhibits macropinocytosis while still supporting autophagy. CARMIL1-WT and -AA mutant cells were generated using the MMTV-PyMT tumor model and HeLa cell lines and validated for CARMIL1 expression by western blot and quantitative PCR and for macropinocytosis by dextran analysis. These cells were evaluated for autophagic flux by western blot for LC3 I/II and by utilizing a GFP-LC3-RFP-LC3ΔG reporter. Our observation that CARMIL1-AA does not impact autophagy enables further investigation of the importance of macropinocytosis in therapeutic resistance and in shaping the tumor microenvironment. Citation Format: Rebecca M Lim, Brandon Chu, Aimee Lara Edinger. A genetic approach to selectively inhibit macropinocytosis while sparing autophagy [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Breast Cancer Research; 2023 Oct 19-22; San Diego, California. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_1):Abstract nr B071.

Cytochrome P450 2C19*2 Genetic Polymorphism in Patients with Acute Coronary Syndrome

Objectives: The study aimed to investigate the association between CP2C19*2 loss of function polymorphism and acute coronary syndrome (ACS) patients receiving Clopidogrel. It compared genotype frequencies of heterozygous GA, homozygous GG, and homozygous AA between ACS patients and healthy controls. The study assessed the statistical significance of the association in the Pakistani cohort. It contributed to understanding the role of genetic polymorphisms in response to Clopidogrel therapy in ACS patients and provided insights into the need for pharmacogenomics testing for patients with CAD, particularly in the Asian population, who are poor metabolizers and require long-term Clopidogrel therapy.&#x0D; Methodology: COHORT Study.&#x0D; Results: The study found no statistically significant association between the CYP2C19*2 loss of function polymorphism and acute coronary syndrome (ACS) in the Pakistani cohort. The frequency of the CP2C19*2 heterozygous GA genotype was 38.3% in ACS patients and 29.5% in control subjects, while the homozygous GG genotype was 58.7% in patients and 59.0% in controls. The homozygous AA genotype was 3.4% in patients and 11.4% in controls.&#x0D; The genotype frequency analysis showed that the wild type GG genotype was lower in patients (58.7%) compared to controls (59.0%), while the mutant AA genotype was also lower in patients (3.4%) compared to controls (11.4%). The heterozygous GA genotype was higher in patients (38.3%) compared to controls (29.5%).&#x0D; The population studied was in Hardy Weinberg equilibrium, with a frequency of mutant allele A at 0.26 and wild type allele G at 0.73.&#x0D; Conclusion: The study concludes that the CYP2C19*2 loss of function polymorphism is not associated with acute coronary syndrome (ACS) in the Pakistani cohort. The distribution of the CP2C19*2 genetic polymorphism was not statistically significant between ACS patients and healthy controls.&#x0D; The genotype frequency analysis showed no significant differences in the distribution of the heterozygous GA, homozygous GG, and homozygous AA genotypes between the patient and control groups.&#x0D; The population studied was in Hardy Weinberg equilibrium, with a frequency of mutant allele A at 0.26 and wild type allele G at 0.73.

Association of Single Nucleotide Polymorphism in VDR, GC Globulin and CYP2R1 with the Risk of Esophageal Cancer.

The proactive role of vitamin D has been well determined in different cancers. The protein that encodes the components of the vitamin D metabolism could appear to play a pivotal role in vitamin D stability and its maintenance. A polymorphism in vitamin-D-receptor (VDR), carrier globulin/binding protein (GC) and cytochrome P-450 family 2, subfamily R, polypeptide 1 (CYP2R1) genes has been predicted to be associated with the development of cancer. This study was designed to detect the association of VDR, GC Globulin and CYP2R1 gene polymorphism with the risk of esophageal cancer in the North-east Indian population. To carry out the study, a total of 100 patients diagnosed with esophageal cancer and 101 healthy controls were enrolled. In a case-control manner, all samples were subjected to do genotype testing for known SNPs on the VDR (rs1544410), GC (rs4588), and CYP2R1 (rs10741657) genes using Restriction-fragment length polymorphism (RFLP) followed by Sanger sequencing. The collected demographic and clinical data were analysed using the statistical software package SPSS v22.0. The VDR haplotype heterozygous TC was found strongly associated with the carcinoma group (OR:1.09, 95%CI:0.67-1.75). The risk factors analysis using the GC globulin rs4588 phenotype, found a positive correlation in terms of mutant AA's harmful influence on the cancer cohort (OR = 1.125, OR=1.125, 95% CI, 0.573-2.206). The influence of the CYP2R1 rs10741657 polymorphism on the malignant cohort revealed that the GG mutant had a significant negative influence on the carcinoma, has an influential role in disease severity ( OR:1.736, at 95% CI; 0.368-8.180). In conclusion, this study revealed the potential association of VDR gene polymorphism in the progression and development of esophageal cancer in north east Indian population cohort.

Rapid Visual Detection of High Nitrogen-Use Efficiency Gene OsGRF4 in Rice (Oryza sativa L.) Using Loop-Mediated Isothermal Amplification Method.

The GROWTH-REGULATING FACTOR4 (OsGRF4) allele is an important target for the development of new high nitrogen-use efficiency (NUE) rice lines that would require less fertilizers. Detection of OsGRF4 through PCR (polymerase chain reaction)-based assay is cumbersome and needs advanced laboratory skills and facilities. Hence, a method for conveniently and rapidly detecting OsGRF4 on-field is a key requirement for further research and applications. In this study, we employed cleaved amplified polymorphic sequences (CAPs) and loop-mediated isothermal amplification (LAMP) techniques to develop a convenient visual detection method for high NUE gene OsGRF4NM73 (OsGRF4 from the rice line NM73). The TC→AA mutation at 1187-1188 bp loci was selected as the target sequence for the OsGRF4NM73 allele. We further employed this method of identification in 10 rice varieties that carried the OsGRF4 gene and results revealed that one variety (NM73) carries the target OsGRF4NM73 allele, while other varieties did not possess the osgrf4 genotype. The optimal LAMP reaction using hydroxynaphthol blue (HNB), a chromogenic indicator, was carried out at 65 °C for 60 min, and the presence of OsGRF4NM73 allele was confirmed by color changes from violet to sky blue. The results of this study showed that the LAMP method can be conveniently and accurately used to detect the OsGRF4NM73 gene in rice.

Epidemiological and Molecular Approaches for a Fatal Feline Panleukopenia Virus Infection of Captive Siberian Tigers (Panthera tigris altaica) in the Republic of Korea.

Feline panleukopenia virus (FPV), a member of the species Protoparvovirus carnivoran1, is one of the most fatal pathogens of domestic and wild carnivores. The virus endemically infects domestic carnivores worldwide and its cross-species transmission threatens endangered wild carnivores, including Siberian tigers. In this study, a fatal FPV infection in endangered Siberian tigers was investigated to trace the origin of the virus and elucidate the reason behind FPV's infection of the vaccinated tigers. Our genetic characterization and phylogenetic analysis revealed that the virus detected in the infected tigers, designated as the KTPV-2305 strain, was closely related to FPV strains circulating in Korean cats, suggesting that it might have been transmitted from stray cats wandering around the zoo. Compared with the prototype FPV reference strains, the KTPV-2305 strain carried three distinct amino acid (aa) mutations in the VP2 protein sequence (I101T, I232V, and L562V) in this study. These three mutations are commonly found in most global FPV strains, including Korean strains, indicating that these mutations are common evolutionary characteristics of currently circulating global FPVs. The reason why the vaccinated tigers were infected with FPV was most likely the insufficient protective immunity of the affected tigress or vaccine failure triggered by the interference of maternal-derived antibodies in the affected tiger cubs. These findings suggest that improved vaccination guidelines are urgently needed to save the lives of wild carnivores from this fatal virus.