Protein Complex Formation Research Articles

Characterization and expression analysis of the B3 gene family during seed development in Akebia trifoliata

BackgroundB3 genes encode transcription factors that play key roles in plant growth and development. However, the specific B3 genes involved in the seed development of Akebia trifoliata remain unexplored.ResultsA total of 72 AktB3 genes were identified and classified into five subfamilies (ARF, LAV, RAV, HSI, and REM) based on phylogenetic analysis. These 72 AktB3 genes were unevenly distributed across 16 chromosomes. Collinear analysis indicated that segmental duplication has played a significant role in the evolution of AktB3 genes, and underwent purification selection. Expression profiling across seed development stages revealed that seven AktB3 genes, particularly from the LAV subfamily (AktABI3, AktFUS3, AktLEC2), were up-regulated at 70 days after flowering (DAF). Notably, the expression of oleosin exhibited a strong positive correlation with LAV subfamily genes, highlighting their potential roles as hub genes in lipid metabolism and seed development. Yeast two-hybrid (Y2H) and yeast one-hybrid (Y1H) experiments confirmed that AktFUS3-1, AktFUS3-2, and AktLEC2 form protein complexes and individually bind to the AktOLE1 promoter, thereby regulating downstream gene expression. These results provide direct evidence of the cooperative role these transcription factors play in controlling lipid metabolism, particularly related to oleosin proteins. Additionally, miRNA sequencing across three seed developmental stages identified 591 miRNAs and 1,673 target gene pairs. A total of 23 AktB3 genes were predicted to be targets of 20 miRNAs, with 11 miRNAs specifically targeting the ARF subfamily genes. Particularly, miR160-x, miR160-z, and miR167-z were predicted to target ARF subfamily genes, potentially influencing seed development. Moreover, the miRNA-B3 regulatory modules, especially involving ARF genes and miR160/167, require further study to clarify their roles in seed development.ConclusionsThese findings contribute valuable resources for future functional studies of the molecular regulatory networks governing seed development in A. trifoliata.

Single-Molecule-Based, Label-Free Monitoring of Molecular Glue Efficacies for Promoting Protein-Protein Interactions Using YaxAB Nanopores.

Modulating protein-protein interactions (PPIs) is an attractive strategy in drug discovery. Molecular glues, bifunctional small-molecule drugs that promote PPIs, offer an approach to targeting traditionally undruggable targets. However, the efficient discovery of molecular glues has been hampered by the current limitations of conventional ensemble-averaging-based methods. In this study, we present a YaxAB nanopore for probing the efficacy of molecular glues in inducing PPIs. Using YaxAB nanopores, we demonstrate single-molecule-based, label-free monitoring of protein complex formation between mammalian target of rapamycin (mTOR) and FK506-binding proteins (FKBPs) triggered by the molecular glue, rapamycin. Owing to its wide entrance and adjustable pore size, in combination with potent electro-osmotic flow (EOF), a single funnel-shaped YaxAB nanopore enables the simultaneous detection and single-molecule-level quantification of multiprotein states, including single proteins, binary complexes, and ternary complexes induced by rapamycin. Notably, YaxAB nanopores could sensitively discriminate between the binary complexes or ternary complexes induced by rapamycin and its analogues, despite the subtle size differences of ∼122 or ∼116 Da, respectively. Taken together, our results provide proof-of-concept for single-molecule-based, label-free, and ultrasensitive screening and structure-activity relationship (SAR) analysis of molecular glues, which will contribute to low-cost, highly efficient discovery, and rational design of bifunctional modality of drugs, such as molecular glues.

Erp57 facilitates ZIKV-induced DNA damage via NS2B/NS3 complex formation.

It is believed that DNA double-strand breaks induced by Zika virus (ZIKV) infection in pregnant women is a main reason of brain damage (e.g. microcephaly, severe brain malformation, and neuropathy) in newborn babies [1,2], but its underlying mechanism is poorly understood. In this study, we report that the depletion of ERp57, a member of the protein disulphide isomerase (PDI) family, leads to the limited production of ZIKV in nerve cells. ERp57 knockout not only suppresses viral induced reactive oxygen species (ROS) mediated host DNA damage, but also decreases apoptosis. Strikingly, DNA damage depends on ERp57-bridged complex formation of viral protein NS2B/NS3. LOC14, an ERp57 inhibitor, restricts ZIKV infection and virus-induced DNA damage. Our work reveals an important role of ERp57 in both ZIKV propagation and virus-induced DNA damage, suggesting a potential target against ZIKV infection.

NFAT5 governs cellular plasticity-driven resistance to KRAS-targeted therapy in pancreatic cancer.

Resistance to KRAS therapy in pancreatic ductal adenocarcinoma (PDAC) involves cellular plasticity, particularly the epithelial-to-mesenchymal transition (EMT), which poses challenges for effective targeting. Chronic pancreatitis, a known risk factor for PDAC, elevates TGFβ levels in the tumor microenvironment (TME), promoting resistance to KRAS therapy. Mechanistically, TGFβ induces the formation of a novel protein complex composed of SMAD3, SMAD4, and the nuclear factor NFAT5, triggering EMT and resistance by activating key mediators such as S100A4. Inhibiting NFAT5 attenuates pancreatitis-induced resistance to KRAS inhibition and extends mouse survival. Additionally, TGFβ stimulates PDAC cells to secrete CCL2, recruiting macrophages that contribute to KRAS bypass through paracrine S100A4. Our findings elucidate the role of TGFβ signaling in EMT-associated KRAS therapy resistance and identify NFAT5 as a druggable target. Targeting NFAT5 could disrupt this regulatory network, offering a potential avenue for preventing resistance in PDAC.

Cyclic Isothiocyanate Goitrin Impairs Lotus japonicus Nodulation, Affects the Proteomes of Nodules and Free Mesorhizobium loti, and Induces the Formation of Caffeic Acid Derivatives in Bacterial Cultures.

The continuous release of glucosinolates into the soil by Brassicaceae root exudation is a prerequisite to maintaining toxic levels of breakdown products such as isothiocyanates (ITCs). ITCs influence plant and microbial diversity in ecosystems, while fungi and Rhizobiaceae are particularly injured. Studies explaining the molecular mechanisms of the negative effects are presently limited. Therefore, we investigated the early effects of cyclic ITC goitrin on proteomes of the host and symbiotic Mesorhizobium loti in the nodules of Lotus japonicus and of free-living bacteria. In the nodules, many host proteins had a higher abundance, among them, peroxidases and pathogenesis-related PR-10 proteins functioning in the abscisic-acid-activated signaling pathway. In the microsymbiont, transporter proteins as a prominent group are enhanced; some proteins involved in N-fixation decreased. The proteomes give a report about the loss of immunity suppression resulting in the termination of symbiosis, which initiates nodule senescence. Free-living M. loti are severely damaged, indicated, i.a., by a decrease in transporter proteins, the assumed candidates for goitrin protein complex formation, and high proteolysis. The production of chicoric acid by the accompanying bacteria is inhibitory for M. loti but connected to goitrin elimination, as confirmed by mass spectrometric (MS) analysis. In summary, the nodulation process is severely affected by goitrin, causing nodule dysfunction and failed nodule development. N deficiency conditions leads to yellowish leaves and leaf abscission.

Giantin mediates Golgi localization of Gal3-O-sulfotransferases and affects salivary mucin sulfation in Sjögren's disease patients.

Sjögren's disease is a chronic autoimmune disease characterized by symptoms of oral and ocular dryness and extra-glandular manifestations. Mouth dryness is not only due to reduced saliva volume but also to alterations in the quality of salivary mucins in these patients. Mucins play a leading role in mucosa hydration and protection, where sulfated and sialylated oligosaccharides retain water molecules at the epithelial surface. The correct localization of glycosyltransferases and sulfotransferases within the Golgi apparatus determines adequate O-glycosylation and sulfation of mucins, which depends on specific golgins that tether enzyme-bearing vesicles. Here, we show that a golgin called Giantin is mislocalized in salivary glands from patients with Sjögren's disease and forms protein complexes with Gal3-O-sulfotransferases (Gal3STs), which change their localization in Giantin knockout and knockdown cells. Our results suggest that Giantin could tether Gal3ST-bearing vesicles and that its altered localization could affect Gal3ST activity, explaining the decreased sulfation of MUC5B observed in salivary glands from patients with Sjögren's disease.

Histone deacetylase 7 activates 6-phosphogluconate dehydrogenase via an enzyme-independent mechanism that involves the N-terminal protein-protein interaction domain.

Histone deacetylase 7 (HDAC7) is a member of the class IIa family of classical HDACs with important roles in cell development, differentiation, and activation, including in macrophages and other innate immune cells. HDAC7 and other class IIa HDACs act as transcriptional repressors in the nucleus but, in some cell types, they can also act in the cytoplasm to modify non-nuclear proteins and/or scaffold signalling complexes. In macrophages, HDAC7 is a cytoplasmic protein with both pro- and anti-inflammatory functions, with the latter activity involving activation of the pentose phosphate pathway (PPP) enzyme 6-phosphogluconate dehydrogenase (6PGD) and the generation of anti-inflammatory metabolite ribulose-5-phosphate. Here, we used ectopic expression systems and biochemical approaches to investigate the mechanism by which HDAC7 promotes 6PGD enzyme activity. We reveal that HDAC7 enzyme activity is not required for its activation of 6PGD and that the N-terminal protein-protein interaction domain of HDAC7 is sufficient to initiate this response. Mechanistically, the N-terminus of HDAC7 increases the affinity of 6PGD for NADP+, promotes the generation of a shorter form of 6PGD, and enhances the formation of higher order protein complexes, implicating its scaffolding function in engagement of the PPP. This contrasts with the pro-inflammatory function of HDAC7 in macrophages, in which it promotes deacetylation of the glycolytic enzyme pyruvate kinase M2 for inflammatory cytokine production.

Binding mechanism and structural characteristics of alloyed protein complex for enhanced solubility of hemp seed protein isolate

Despite the numerous health benefits and high digestibility of hemp seed protein isolate (HPI), its low solubility at neutral pH limits its utilization in the food industry. Therefore, we subjected insoluble HPI and soluble mung bean protein isolate (MBPI) to pH co-shifting under extremely alkaline conditions to form an alloyed protein complex (A-HM). At a mass ratio of HPI:MBPI of 50:50, A-HM exhibited the highest solubility (95.30 ± 0.99 %), and also had high resistance to heat treatment. Native PAGE demonstrated the formation of alloyed protein complexes, and particle size analysis revealed that A-HM exhibited small particle sizes and dispersion in water without aggregation of HPI. Owing to their small size, numerous hydrophobic residues and aromatic ring of HPI were exposed on the surface. Hydrophobic interactions predominantly governed the binding force involved in the formation of A-HM. Our findings may enhance HPI applications in the food industry, particularly in plant-based beverages.

Identification of Homeobox Transcription Factors in a Dimorphic Fungus Talaromyces marneffei and Protein-Protein Interaction Prediction of RfeB.

Talaromyces marneffei is a thermally dimorphic fungus that can cause life-threatening systemic mycoses, particularly in immunocompromised individuals. Fungal homeobox transcription factors control various developmental processes, including the regulation of sexual reproduction, morphology, metabolism, and virulence. However, the function of homeobox proteins in T. marneffei has not been fully explored. Here, we searched the T. marneffei genome for the total homeobox transcription factors and predicted their biological relevance by performing gene expression analysis in different cell types, including conidia, mycelia, yeasts, and during phase transition. RfeB is selected for further computational analysis since (i) its transcripts were differentially expressed in different phases of T. marneffei, and (ii) this protein contains the highly conserved protein-protein interaction region (IR), which could be important for pathobiology and have therapeutic application. To assess the structure-function of the IR region, in silico alanine substitutions were performed at three-conserved IR residues (Asp276, Glu279, and Gln282) of RfeB, generating a triple RfeB mutated protein. Using 3D modeling and molecular dynamics simulations, we compared the protein complex formation of wild-type and mutated RfeB proteins with the putative partner candidate TmSwi5. Our results demonstrated that the mutated RfeB protein exhibited increased free binding energy, elevated protein compactness, and a reduced number of atomic contacts, suggesting disrupted protein stability and interaction. Notably, our model revealed that the IR residues primarily stabilized the RfeB binding sites located in the central region (CR). This computational approach for protein mutagenesis could provide a foundation for future experimental studies on the functional characterization of RfeB and other homeodomain-containing proteins in T. marneffei.

TERT upregulation promotes cell proliferation via degradation of p21 and increases carcinogenic potential.

Telomerase reverse transcriptase (TERT) gene aberration is detectable in >80% of cases with hepatocellular carcinoma (HCC). TERT reactivation is essential for cellular immortalization because it stabilizes telomere length, although the role of TERT in hepatocarcinogenesis remains unelucidated. To elucidate the significance of aberrant TERT expression in hepatocytes in inflammation-associated hepatocarcinogenesis, we generated Alb-Cre;TertTg mice, which overexpress TERT in the liver and examined their phenotype during chronic inflammation. Based on transcriptome data from the liver tissue of Alb-Cre;TertTg mice, we examined the role of TERT in hepatocarcinogenesis in vitro. We also evaluated the relationship between TERT and cell-cycle-related molecules, including p21, in HCC samples. The liver tumor development rate was increased by TERT overexpression during chronic inflammation, especially in the absence of p53 function. Gene set enrichment analysis of liver tissues revealed that gene sets related to TNF-NFκB signaling, cell cycle, and apoptosis were upregulated in Alb-Cre;TertTg liver. A luciferase reporter assay and immunoprecipitation revealed that TERT interacted with NFκB p65 and enhanced NFκB promoter activity. On the other hand, TERT formed protein complexes with p21, cyclin A2, and cyclin E and promoted ubiquitin-mediated degradation of p21, specifically in the G1 phase. In the clinical HCC samples, TERT was highly expressed but p21 was conversely downregulated, and TERT expression was associated with the upregulation of molecules related to the cell cycle. Taken together, the aberrant upregulation of TERT increased NFκB promoter activity and promoted cell cycle progression via p21 ubiquitination, leading to hepatocarcinogenesis. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Interactions of White Mugwort (Artemisia lactiflora Wall.) Extract with Food Ingredients during In Vitro Gastrointestinal Digestion and Their Impact on Bioaccessibility of Polyphenols in Various Model Systems.

The bioaccessibility of phytochemicals is an important factor for new functional food design. The interaction of white mugwort extract (FE) and food ingredients (coconut oil, egg white albumen, brown rice powder, inulin, and mixtures thereof) was determined after in vitro digestion to inform the development of a functional soup for an aging population. Coconut oil exerted a protective effect on polyphenols, showing the highest bioaccessibility (62.9%) and antioxidant activity after intestinal digestion (DPPH 12.38 mg GAE/g DW, FRAP 0.88 mol Fe(ll)/g DW). In contrast, egg white albumen had the most significant negative effect on the polyphenol stability, resulting in the lowest bioaccessibility (12.49%). Moreover, FE promoted the emulsion stability and delayed starch digestion by inhibiting amylase activity via non-specific polyphenol-protein interactions, resulting in a decrease in the total reducing sugars (TRS) released during digestion. It also limited the protein digestion, probably due to the complex formation of polyphenols and proteins, consequently reducing the bioaccessibility of both amino acids and polyphenols. These findings provide useful information for designing functional food products that could promote the bioaccessibility and bioactivity of natural extracts.

Embryonic Genome Activation (EGA) Occurred at 1-Cell Stage of Embryonic Development in the Mud Crab, Scylla paramamosain, Revealed by RNA-Seq.

As a prerequisite for the success of embryo development, embryonic genome activation (EGA) is an important biological event in which zygotic gene products in the embryo are activated to replace maternal-derived transcripts. Although EGA has been extensively studied in a large number of vertebrates and invertebrates, there is a lack of information regarding this event in crustacean crab. In this study, the timing of EGA was confirmed by examining a transcriptomic dataset of early embryonic development, including mature oocytes and embryos through six early developmental stages, and signaling pathways associated with EGA were identified in the mud crab, S. paramamosain. The comprehensive transcriptomic data identified a total of 53,915 transcripts from these sequencing samples. Notable transcriptomic change was evident at the 1-cell stage, indicated by a 36% transcript number shift and a reduction in transcript fragment length, compared to those present in the mature oocytes. Concurrently, a substantial increase in the expression of newly transcribed transcripts was observed, with gene counts reaching 3485 at the 1-cell stage, indicative of the onset of EGA. GO functional enrichment revealed key biological processes initiated at the 1-cell stage, such as protein complex formation, protein metabolism, and various biosynthetic processes. KEGG analysis identified several critical signaling pathways activated during EGA, including the "cell cycle," "spliceosome," "RNA degradation", and "RNA polymerase", pathways. Furthermore, transcription factor families, including zinc finger, T-box, Nrf1, and Tub were predominantly enriched at the 1-cell stage, suggesting their pivotal roles in regulating embryonic development through the targeting of specific DNA sequences during the EGA process. This groundbreaking study not only addresses a significant knowledge gap regarding the developmental biology of S. paramamosain, especially for the understanding of the mechanism underlying EGA, but also provides scientific data crucial for the research on the individual synchronization of seed breeding within S. paramamosain aquaculture. Additionally, it serves as a reference basis for the study of early embryonic development in other crustacean species.

Mutations in the N-domain of aryl hydrocarbon receptor interacting protein affect interactions with heat shock protein 90β and phosphodiesterase 4A5

The aryl hydrocarbon receptor interacting protein (AIP) is a cytoplasmic molecular co-chaperone and tumour suppressor that assists in protein stability and complex formation involving the aryl hydrocarbon receptor. Germline mutations in the AIP gene predispose to pituitary tumourigenesis with patients exhibiting an aggressive clinical phenotype. Full length AIP proteins harbouring N-domain mutations (R9Q, R16H, V49 M and K103R) were purified from E.coli utilizing a methodology that maintained structural integrity and monomeric stability. Mutations did not significantly affect the thermal stability of the protein and caused no overall disruptive effect in the protein structure. The mutations studied lowered the binding affinity of AIP towards two of its binding partners; heat shock protein 90β and phosphodiesterase 4A5 (PDE4A5). The inhibition of phosphodiesterase activity by AIP was also greatly reduced by all mutants. While previously published data has mainly concentrated on the tetratricopeptide repeats of the C-domain of AIP, we present clear evidence that AIP N-domain mutations play a significant role in two protein:protein interactions with partner proteins. The complex interactome of AIP suggests that any observable change in one or more of its binding partners cannot be disregarded as it may have repercussions on other biochemical pathways.

Plant resistance to pathogens as a result of gene interaction

Modern information on the genomics of plants and plants’ pathogens as well the achievements of molecular biology have made it possible to state the participation of gene products, proteins, in the organization of molecular complexes that are assembled to implement a certain character of the phenotype. The character of plant “resistance/sensitivity” to a certain biotic factor is also interesting because there is an interaction not only between the genes of one organism, but between the genes of organisms that lie in different kingdoms of life.Plant resistance to pathogens can be passive (provided mainly by characters of plant morphology) and active. Active resistance is formed as a result of the penetration of the pathogen or its elicitors and effectors into the plant. Active protection of the plant at the molecular level is expressed in the launch of the MAPK cascade, the accumulation of reactive oxygen species, and an increase in the flow of calcium ions to the cell. Active protection can be implemented on two levels. The first level, RTI (PAMP Triggered Immunity), develops in response to plant contact with a wide range of non-adapted pathogens. The resistance (immunity) that is formed in this case is called non-specific, or horizontal, or quantitative. The molecular instrument for initiating the defensive reaction is the PRR (Pattern Recognition Receptors). Adapted pathogens are able to overcome RTI by sending effectors to plant cells. These are protein molecules whose function is to create conditions within the cell that are more permissive to the pathogen. The effector can be recognized by the plant’s specific NLR (Nod-Like Receptors), and complementation occurs between the two. There are other specific plant molecules, nonNLR, with a different type of protein product interaction for recognition. In both cases, the second level of protection, ETI (Effector Triggered Immunity), develops. The set of molecular processes that occur at the second level of protection does not differ from the set of the first level, but the processes occur more intensively and are accompanied by the death of the affected cells. This prevents the further spread of the pathogen throughout the plant. The molecular events of the first and second levels of protection are not isolated. The interaction between them involving the products of plant genes and pathogen genes is described by the “zig-zag-zig”-model, invasion model, and the integrated iceberg model. The interaction of plant genes for effector recognition is described by the “guard” and “decoy” models. To initiate a defensive reaction, plant receptors, which can sometimes differentiate into sensors and helpers, form protein complexes, resistosomes.

NLRP3 inflammasomes as a target for hesperidin and diosmin flavonoids in varicose vein disease and its complications

Varicose vein disease of the lower extremities is an inflammatory disorder with abnormal structure and functional activity of the venous valves, venous walls and cells, as well as with abnormal activity of the infiltrating leukocytes. The abnormally changed varicose vein are characterized by increased venous pressure, blood accumulation and congestion, ischemia, and metabolic and energy turnover derangement, which result in clinical manifestations of complications, such as pain, edema and formation of trophic ulcers. For many years, flavonoids have been used to treat varicose veins. The most effective flavonoids used in varicose vein disease and its complications, are hesperidin and diosmin, as well as their combinations. The review sets forth the state-of-the-art knowledge on the universal inflammatory processes playing a leading role in the pathophysiology of many cardiovascular disorders, including venous ones. In the recent years, it has been found that one of the main causes of inflammation is the formation of intracellular protein complexes (inflammasomes), which both produce a set of proinflammatory cytokines and are responsible for their excretion from the cells. In addition, inflammasomes control the development of regulated necrosis (pyroptosis) that takes part in the process of ulceration. The inflammasome activity can be modified by various mechanisms, of which the gene independent synthesis of the inflammasomal proteins has been recognized as the leading one. It has been shown that flavonoids inhibit the activation of a key factor NF-kappa B and suppress the synthesis of proteins, including NOD-like receptor protein 3 (NLRP3) inflammasome components, decrease the expression of NLRP3 receptor, protein ASC and caspase 1, as well as diminish interleukin 1 beta, interleukin 6 and tumor necrosis factor-alpha expression. Thus, this is the explanation of positive effects observed with the use of hesperidin, diosmin and their combination in clinical practice.

Abstract Tu074: A Potential Link Between Stress Kinase JNK2 and AKAP-1 in Catecholamine-Induced Acute Heart Failure

Takotsuba Syndrome (TTS) is a type of emotional/physical stress-induced heart failure (HF). Stress-elevated catecholamines activate adrenergic signaling. Cardiac A-Kinase Anchoring Protein-1 (AKAP1) is known to regulate the adrenergic signaling via protein complex formation and phosphorylation. We recently discovered that activation of the stress response kinase JNK2 is critical in HF onset. Whether AKAP1 is involved with stress-activated JNK2 and HF onset remains completely unknown. Isoproterenol (Iso; synthetic catecholamine) effects on JNK2 activation were assessed in left ventricles (LV) from Iso-treated wildtype (WT) mice (67 mg/kg i.p., 2 days) and in heterologous HEK-RyR2 cells (inducible cardiac ryanodine receptor-2; myocyte mimic; 5 mM Iso, 24 h). A JNK2 effect on cardiac function was reflected by cardiac output (CO) using echocardiography in cardiac-specific MKK7D (inducible overexpression of active MKK7D; a JNK upstream activator) and MKK7D-JNK2KD (50% JNK2 knockdown in MKK7D) mice. The AKAP1-JNK2 link was assessed using immunoprecipitation (IP) and immunoblotting in tGFP -JNK2 and/or FLAG -AKAP1 transfected HEK293 cells. Iso-WT LV had increased JNK phosphorylation (JNK-p, activated) and reduced SERCA2 (a hallmark of HF) vs controls. Likely, MKK7-induction in MKK7D LV increased JNK2 and JNK-p (vs WT-littermates; p<0.05, n=5,4), which led to reduced CO by 68% (n=5,6, p<0.01) and downregulated SERCA2 by 79% (p<0.01, n=4,8), also evidenced by preserved CO and SERCA2 in MKK7D-JNK2KD mice (50% ablated JNK2; n=9). Moreover, Iso treatment in HEK-RyR2 cells activated JNK2, but not JNK1, compared to sham controls. Intriguingly, we found that JNK2 was associated with AKAP1, given the co-IP of tGFP -JNK2 with anti- FLAG antibody pulldown of FLAG -AKAP1 co-transfected HEK293 cells (n=3). Further, overexpressed FLAG -AKAP1 increased the phosphorylation of co-transfected tGFP -JNK2 as well as endogenous JNK (p<0.01 & p<0.001, n=3,3), while the notable JNK downstream target c-Jun also showed increased phosphorylation (c-Jun-p; p<0.05, n=3,3), supporting a previously unrecognized role for AKAP1 in JNK2 activation. In total, our findings suggest that stress activates JNK2 via an adrenergic-AKAP1 activation pathway to drive HF/TTS onset.

LRPPRC and SLIRP synergize to maintain sufficient and orderly mammalian mitochondrial translation.

In mammals, the leucine-rich pentatricopeptide repeat protein (LRPPRC) and the stem-loop interacting RNA-binding protein (SLIRP) form a complex in the mitochondrial matrix that is required throughout the life cycle of most mitochondrial mRNAs. Although pathogenic mutations in the LRPPRC and SLIRP genes cause devastating human mitochondrial diseases, the in vivo function of the corresponding proteins is incompletely understood. We show here that loss of SLIRP in mice causes a decrease of complex I levels whereas other OXPHOS complexes are unaffected. We generated knock-in mice to study the in vivo interdependency of SLIRP and LRPPRC by mutating specific amino acids necessary for protein complex formation. When protein complex formation is disrupted, LRPPRC is partially degraded and SLIRP disappears. Livers from Lrpprc knock-in mice had impaired mitochondrial translation except for a marked increase in the synthesis of ATP8. Furthermore, the introduction of a heteroplasmic pathogenic mtDNA mutation (m.C5024T of the tRNAAla gene) into Slirp knockout mice causes an additive effect on mitochondrial translation leading to embryonic lethality and reduced growth of mouse embryonic fibroblasts. To summarize, we report that the LRPPRC/SLIRP protein complex is critical for maintaining normal complex I levels and that it also coordinates mitochondrial translation in a tissue-specific manner.

What are the main proteins in the hemolymph of Haemaphysalis flava ticks?

Haemaphysalis flava is a notorious parasite for humans and animals worldwide. The organs of H. flava are bathed in hemolymph, which is a freely circulating fluid. Nutrients, immune factors, and waste can be transported to any part of the body via hemolymph. The main soluble components in hemolymph are proteins. However, knowledge of the H. flava proteome is limited. The hemolymph was collected from fully engorged H. flava ticks by leg amputation. Hemolymph proteins were examined by both blue native polyacrylamide gel electrophoresis (BN-PAGE) and sodium dodecyl sulfate PAGE (SDS-PAGE). Proteins extracted from the gels were further identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Two bands (380 and 520 kDa) were separated from tick hemolymph by BN-PAGE and were further separated into four bands (105, 120, 130, and 360 kDa) by SDS-PAGE. LC-MS/MS revealed that seven tick proteins and 13 host proteins were present in the four bands. These tick proteins mainly belonged to the vitellogenin (Vg) family and the α-macroglobulin family members. In silico structural analysis showed that these Vg family members all had common conserved domains, including the N-terminus lipid binding domain (LPD-N), the C-terminus von Willebrand type D domain (vWD), and the domain of unknown function (DUF). Additionally, two of the Vg family proteins were determined to belong to the carrier protein (CP) by analyzing the unique N-terminal amino acid sequences and the cleaving sites. These findings suggest that the Vg family proteins and α-macroglobulin are the primary constituents of the hemolymph in the form of protein complexes. Our results provide a valuable resource for further functional investigations of H. flava hemolymph effectors and may be useful in tick management.

Zinc(II) Induced Alzheimer’s Disease Prevention and Progression With Early, Middle and Lately Stages

Zinc(Ⅱ) induced Alzheimer’s Disease (AD) prevention and suppressive progression with early, middle, and lately stages are elucidated, and subsequently zinc binding molecular mechanism on each Aβ peptide and Tau protein in progressing stages is clarified. Zinc homeostasis regulates MCI and AD prevention, in which ZnCl2 could prevent AD pathology by that zinc can reduce β-Amyloid (Aβ) and Tau proteins. Zinc transporters may allow the novel therapies that ZnT-6 functions to a likely site of Aβ generation. At AD progression with early stage, zinc-induced aggregation of Aβ peptides and tau hyperphosphorylation on amyloid and tau aggregation consider the involvement of environmental zinc in Aβ and tau pathology. Zinc can suppress spreading of the Aβ peptide and the Tau protein that elemental zinc 150 mg daily is showed to be evident for an improvement of memory, understanding, communication, and social contact in AD. Zinc induced middle stage AD progression is pathologically characterized by the deposition of Aβ plaques and hyperphosphorylated Tau Proteins (p-tau). Zinc Finger Proteins (ZNFs) regulate the accumulation of tau proteins to affect the Neurofibrillary Tangles (NFTs), resulting in the formation of NFTs, and can inhibit protein phosphatase, promoted abnormal phosphorylation of tau protein. Zinc(Ⅱ) can prevent heavy stage AD with pathological deposits of Senile Plaques (SPs) and NFTs that the tau-zinc interaction will help understanding the zinc-related tau regulation or aggregation processes in both physiological and pathological conditions. Zinc accelerates the fibrillization of human Tau and thereby increases Tau toxicity in neuronal cells with zinc exacerbated tauopathic deficits. Zinc induced toxic Reactive Oxygen Species (ROS) generation and hyperphosphorylated tau cause oxidative stress and neurotoxicity, leading to hyperphosphorylated tau damages. Zinc(Ⅱ) binding AD molecular mechanism on Aβ and Tau proteins is that Zn2+ ions which having Zn2+ ions-centered tetrahedral geometric coordination pattern and Zn-CysHis Ligands complexes with tetrahedral geometry formed, bind with Aβ and Tau proteins in each three AD progressing stages, causing Zn2+ ions-each stages protein complex formations and oxidative stress to Aβ and Tau protein cells, leading the Zn-CysHis Ligands complexes to molecular and apoptosis activities of synaptic cells.

Cotton BOP1 mediates SUMOylation of GhBES1 to regulate fibre development and plant architecture.

The Arabidopsis BLADE-ON-PETIOLE (BOP) genes are primarily known for their roles in regulating leaf and floral patterning. However, the broader functions of BOPs in regulating plant traits remain largely unexplored. In this study, we investigated the role of the Gossypium hirsutum BOP1 gene in the regulation of fibre length and plant height through the brassinosteroid (BR) signalling pathway. Transgenic cotton plants overexpressing GhBOP1 display shorter fibre lengths and reduced plant height compared to the wild type. Conversely, GhBOP1 knockdown led to increased plant height and longer fibre, indicating a connection with phenotypes influenced by the BR pathway. Our genetic evidence supports the notion that GhBOP1 regulates fibre length and plant height in a GhBES1-dependent manner, with GhBES1 being a major transcription factor in the BR signalling pathway. Yeast two-hybrid, luciferase complementation assay and pull-down assay results demonstrated a direct interaction between GhBOP1 and GhSUMO1, potentially forming protein complexes with GhBES1. In vitro and in vivo SUMOylation analyses revealed that GhBOP1 functions in an E3 ligase-like manner to mediate GhBES1 SUMOylation and subsequent degradation. Therefore, our study not only uncovers a novel mechanism of GhBES1 SUMOylation but also provides significant insights into how GhBOP1 regulates fibre length and plant height by controlling GhBES1 accumulation.