Protein Motifs Research Articles

Writers, readers, and erasers of N6-Methyladenosine (m6A) methylomes in oilseed rape: identification, molecular evolution, and expression profiling

Backgroundm6A RNA modifications are the most prevalent internal modifications in eukaryotic mRNAs and are crucial for plant growth and development, as well as for responses to biotic or abiotic stresses. The modification is catalyzed by writers, removed by erasers, and decoded by various m6A-binding proteins, which are readers. Brassica napus is a major oilseed crop. The dynamic regulation of m6A modifications by writers, erasers, and readers offers potential targets for improving the quality of this crop.ResultsIn this study, we identified 92 m6A-regulatory genes in B. napus, including 13 writers, 29 erasers, and 50 readers. A phylogenetic analysis revealed that they could be further divided into four, three, and two clades, respectively. The distribution of protein motifs and gene structures among members of the same clade exhibited notable similarity. During the course of evolution, whole genome duplication (WGD) and segmental duplication were the primary drivers of the expansion of m6A-related gene families. The genes were subjected to rigorous purification selection. Additionally, several sites under positive selection were identified in the proteins. RNA-seq and quantitative real-time PCR (qRT-PCR) expression analyses revealed that the identified Bnam6As exhibit tissue-specific expression patterns, as well as their expression patterns in response to various abiotic and biotic stresses. The 2000 bp sequence upstream of Bnam6As contained a number of cis-acting elements that regulate plant growth and environmental response. Furthermore, the protein interaction network revealed their interactions with a number of proteins of significant functional importance.ConclusionThe identification of m6A modifiers in oilseed rape and their molecular evolution and expression profiling have revealed potential functions and molecular mechanisms of m6A, thus establishing a foundation for further functional validation and molecular breeding.

Phylogenetic and Expression Analysis of SBP-Box Gene Family to Enhance Environmental Resilience and Productivity in Camellia sinensis cv. Tie-guanyin

Tieguanyin tea, a renowned oolong tea, is one of the ten most famous teas in China. The Squamosa Promoter Binding Protein (SBP)-box transcription factor family, widely present in plants, plays a crucial role in plant development, growth, and stress responses. In this study, we identify and analyze 22 CsSBP genes at the genome-wide level. These genes were distributed unevenly across 11 chromosomes. Using Arabidopsis thaliana and Solanum lycopersicum L. as model organisms, we constructed a phylogenetic tree to classify these genes into six distinct subfamilies. Collinearity analysis revealed 20 homologous gene pairs between AtSBP and CsSBP, 21 pairs between SiSBP and CsSBP, and 14 pairs between OsSBP and CsSBP. Cis-acting element analysis indicated that light-responsive elements were the most abundant among the CsSBP genes. Protein motif, domain, and gene architecture analyses demonstrated that members of the same subgroup shared similar exon–intron structures and motif arrangements. Furthermore, we evaluated the expression profiles of nine CsSBP genes under light, shade, and cold stress using qRT-PCR analysis. Notably, CsSBP1, CsSBP17, and CsSBP19 were significantly upregulated under all three stresses. This study provides fundamental insights into the CsSBP gene family and offers a novel perspective on the mechanisms of SBP transcription factor-mediated stress responses, as well as Tieguanyin tea’s adaptation to environmental variations.

In silico analysis of trehalose biosynthesis genes provides clues to reveal its roles in Avicennia marina adaptation to tidal submergence.

Trehalose has an important function for alleviating various abiotic stress in plants. Nevertheless, the functional and evolutionary characteristics of trehalose biosynthesis genes in mangrove plants is not documented. Here, using typical mangrove Avicennia marina, we found the trehalose content decreased in the roots and leaves and T6P increased significantly in the leaves under tidal submergence. Then, the basic physicochemical properties and gene structure of trehalose biosynthesis genes (AmTPS and AmTPP), and the conserved domain and motifs of AmTPS and AmTPP proteins were analyzed. The collinearity analysis and Ka/Ks values indicated that AmTPS and AmTPP are evolutionarily conserved. Tissue-specific expression profiling showed that most AmTPS and AmTPP genes have tissue specificity. RNA-Seq analysis showed that five AmTPS genes were markedly up-regulated in A. marina treated with tidal submergence. Subcellular localization analysis revealed three genes including AmTPS10B, AmTPS11A and AmTPS11C out of these five up-regulated AmTPS genes work in plasma membrane, cytoplasm and nucleus. Finally, integrative analysis of bioinformatics and RNA-Seq analysis were performed to excavate transcription factors that may regulate AmTPS and AmTPP genes in A. marina response to submergence. Taken together, these findings provide new insights into the response to tidal submergence in A. marina at the aspect of trehalose.

Systematic identification and analysis of the HSP70 genes reveals MdHSP70-38 enhanced salt tolerance in transgenic tobacco and apple.

Heat shock protein 70 (HSP70) is a class of important molecular chaperones that are involved in protein folding, stabilization, and maturation, and play a vital role in plant growth and response to environmental stress. Apple trees frequently suffer from different-degree salt stress, which seriously affects their growth, quality, and yield. However, whether HSP70 genes are involved in salt tolerance is unexplored in apple. In this study, 67 MdHSP70 genes were identified and unevenly distributed on 17 apple chromosomes. Gene structure and protein motif analysis revealed that MdHSP70 genes in the same subgroup have similar intron phase and motif organization, further supporting the phylogenetic results. RNA-seq analysis showed the expression level of nine of 67 MdHSP70 genes was induced by salt stress. Subsequent qRT-PCR analysis revealed that MdHSP70-38 was dramatically up-regulated in response to salt stress. The overexpression of MdHSP70-38 in transgenic tobacco and apple improved salt stress tolerance, which was associated with less electrolyte leakage and malondialdehyde (MDA), as well as diminished accumulation of hydrogen peroxide (H2O2) and superoxide radicals (O2-). Our findings demonstrated that MdHSP70-38 played a positive regulatory role in salt tolerance in tobacco and apple, and provided a promising candidate gene in genetic applications for improving salt tolerance.

Genome-wide identification and comparative analysis of the AP2/ERF gene family in Prunus dulcis and Prunus tenella: expression of PdAP2/ERF genes under freezing stress during dormancy

The AP2/ERF (APETALA2/ethylene responsive factor) transcription factor family, one of the largest in plants, plays a crucial role in regulating various biological processes, including plant growth and development, hormone signaling, and stress response. This study identified 114 and 116 AP2/ERF genes in the genomes of 'Wanfeng' almond (Prunus dulcis) and 'Yumin' wild dwarf almond (Prunus tenella), respectively. These genes were categorized into five subfamilies: AP2, DREB, ERF, RAV, and Soloist. The PdAP2/ERF and PtAP2/ERF members both demonstrated high conservation in protein motifs and gene structures. Members of both families were unevenly distributed across eight chromosomes, with 30 and 27 pairs of segmental duplications and 15 and 18 pairs of tandem repeated genes, respectively. The promoter regions of PdAP2/ERF and PtAP2/ERF family members contained numerous important cis-elements related to growth and development, hormone regulation, and stress response. Expression pattern analysis revealed that PdAP2/ERF family members exhibited responsive characteristics under freezing stress at different temperatures in perennial dormant branches. Quantitative fluorescence analysis indicated that PdAP2/ERF genes might be more intensely expressed in the phloem of perennial dormant branches of almond, with the opposite trend observed in the xylem. This study compared the characteristics of PdAP2/ERF and PtAP2/ERF gene family members and initially explored the expression patterns of PdAP2/ERF genes in the phloem and xylem of perennial dormant branches. The findings provide a theoretical foundation for future research on almond improvement and breeding, as well as the molecular mechanisms underlying resistance to freezing stress.

P-788. Exploring β-Lactam Interactions with DacB1: Unraveling Optimal Therapies for Combating Drug-Resistant Mycobacterium tuberculosis

Abstract Background Mtb is a global health problem. DacB1, a D, D-carboxypeptidase, involved in Mtb peptidoglycan biosynthesis, is a promising target for β-lactam antibiotics (BLs) underutilized in Mtb treatment. Dual BL therapy may inactivate multiple targets in the peptidoglycan synthesis pathway (“target redundancy”). Modeling studies with meropenem (MEM), showed that the active site of DacB1 encompasses three penicillin-binding protein motifs: S121XXK124, S176XN178, and K282TG284 (PDB 4PPR). We explored the structure-activity relations, SAR, between DacB1 and other BLs to gain insight into optimal inhibitors for this important drug target. Tab. 1: β-lactam and β-lactamase Inhibitor MICs for Mtb H37Rv, H37Ra and representative Clinical Isolates Methods Minimum inhibitory concentrations (MICs) of BLs and β-lactamase inhibitors (BLIs) against Mtb H37Ra, H37Rv, and representative clinical isolates were tested via broth microdilution. Timed electrospray ionization mass spectrometry captured acyl-enzyme adducts of DacB1 and BLs [amoxicillin (AMX), ceftriaxone (CRO), tebipenem (TBP), imipenem (IPM), MEM] or BLIs [clavulanate (CLA), sulbactam (SUL)]. Molecular docking analyses of MEM, IPM, TBP, and Michaelis-Menten complexes, were conducted.Fig.1:The 2D representation of Michaelis-Menten complexes of DacB1 and IPM (A.), MEM (B.), and TPB (C.) with the formation of initial interactions. The carbonyl group of all the carbapenems is positioned into the oxyanion hole fromed by the catalytic Ser121:N and by Tyr285 amide. the hydroxyethyl group on the β-lactam ring present on all carbapenes produce a hydrophobic interaction with Leu218 and helps the initial positioning od the carbonyl into the oxyanion hole of DacB1. The C1 methyl group in both MEM and TBP, with additional hydrophobic interactions (B. and C.), contribute to the slower acyl-enzyme formation fro those compounds. Results MICs for IPM, MEM, and CRO ranged from 0.5 → >64, 1 → 32, and 0.25 → 16 µg/mL respectively (Tab. 1). Combining IPM or MEM with CRO further lowered MICs up to 32-fold (0.13 → 4 µg/mL), all within clinically achievable concentrations. Acyl-enzyme adducts of DacB1 (MW = 34414 Da) with carbapenems were captured; but not with AMX, CRO, or BLIs even after 120 min incubation. DacB1-IPM complexes were detected with 5 min incubation (Δ+299 Da) while at 15 min and 30 min for -MEM (Δ+383 Da) and -TBP (Δ+384 Da) complexes respectively. Conclusion IPM preferentially binds to DacB1 compared to MEM and TBP, and BLs, shedding light on crucial SAR for drug development. We postulate that the carbonyl group present in all carbapenems assists with positioning into the oxyanion hole of DacB1. However, the C1 methyl in MEM and TBP with their additional hydrophobic interactions contribute to steric hindrance and slower acyl-enzyme formation (Fig. 1). This study advances our understanding of the molecular mechanisms governing DacB1 interactions with BLs, offering insights into how carbapenems may inhibit another important BL target in Mtb peptidoglycan synthesis. Disclosures All Authors: No reported disclosures

Genome-wide identification and expression analysis of GRAS transcription factors under cold stress in diploid and triploid Eucalyptus

The GRAS [GRI (Gibberellic Acid Insensitive), RGA (Repressor of GAI-3 mutant), and SCR (Scarecrow)] transcription factors play a pivotal role in the development and stress responses of plants. Eucalyptus is an important fast-growing tree species worldwide, yet its poor cold tolerance limits its cultivation range. This study conducted a bioinformatics analysis of Eucalyptus grandis GRAS family and investigated the expression patterns of GRAS genes in different ploidy Eucalyptus under cold treatment. This study identified 92 EgrGRAS genes, which were divided into eight subfamilies. Interspecies synteny analysis found that E. grandis and Populus trichocarpa have more syntenic GRAS gene pairs. Chromosome localization analysis revealed that 90 EgrGRAS genes were found to be unevenly distributed across 11 chromosomes. Gene structure analysis found similar intron-exon structures in EgrGRAS genes. Protein motif analysis revealed that proteins within the same subfamily have certain structural similarities. The physical and chemical properties of the proteins encoded by EgrGRAS genes vary, but the ranges of amino acid numbers, molecular weights, and isoelectric points (pI) are similar to those of GRAS proteins from other species. Subcellular localization prediction using software found that 56 members of EgrGRAS family are localized in the nucleus, with a few members localized in the cytoplasm, chloroplasts, and mitochondria. Tobacco subcellular localization experiments verified a nuclear-localized GRAS transcription factor. Cis-acting element analysis predicted that EgrGRAS genes are involved in the growth as well as the response to hormones, light induction, and low-temperature stress. Transcriptome data analysis and quantitative real-time PCR (qRT-PCR) experiments in diploid and triploid Eucalyptus urophylla found that some EgrGRAS genes exhibited upregulated expression under different cold treatment durations, with certain genes from the LISCL, PAT1, and DELLA subfamilies significantly upregulated in triploid Eucalyptus. These EgrGRAS transcription factors may play an important role in Eucalyptus response to cold stress. The study lays a molecular foundation for the breeding of cold-resistant Eucalyptus varieties.

Conservation of OFD1 Protein Motifs: Implications for Discovery of Novel Interactors and the OFD1 Function

OFD1 is a protein involved in many cellular processes, including cilia biogenesis, mitotic spindle assembly, translation, autophagy and the repair of double-strand DNA breaks. Despite many potential interactors identified in high-throughput studies, only a few have been directly confirmed with their binding sites identified. We performed an analysis of the evolutionary conservation of the OFD1 sequence in three clades: 80 Tetrapoda, 144 Vertebrata or 26 Animalia species, and identified 59 protein-binding motifs localized in the OFD1 regions conserved in various clades. Our results indicate that OFD1 contains 14 potential post-translational modification (PTM) sites targeted by at least eight protein kinases, seven motifs bound by proteins recognizing phosphorylated aa residues and a binding site for phosphatase 2A. Moreover, OFD1 harbors both a motif that enables its phosphorylation by mitogen-activated protein kinases (MAPKs) and a specific docking site for these proteins. Generally, our results suggest that OFD1 forms a scaffold for interaction with many proteins and is tightly regulated by PTMs and ligands. Future research on OFD1 should focus on the regulation of OFD1 function and localization.

DExD-box RNA helicases in human viral infections: pro- and anti-viral functions.

Viruses have co-evolved with their hosts, intertwining their life cycles. As a result, components and pathways from a host cell's processes are appropriated for virus infection. This review examines the host DExD-box RNA helicases known to influence virus infection during human infections. We have identified 42 species of viruses (28 genera and 21 families) whose life cycles are modulated by at least one, but often multiple, DExD-box RNA helicases. Of these, 37 species require one or multiple DExD-box RNA helicases for efficient infections, i.e., in these cases the DExD-box RNA helicases are pro-viral. However, similar evolutionary processes have also led to cellular responses that combat viral infections. In humans, these responses comprise intrinsic and innate immune reactions initiated and regulated by some of the same DExD-box RNA helicases that act as pro-viral helicases. Currently, anti-viral DExD-box RNA helicase responses to viral infections are noted in 23 viral species. Notably, most studied viruses are linked to severe, life-threatening diseases, leading many researchers to focus on DExD-box RNA helicases as potential therapeutic targets. Thus, we present examples of host-directed therapies targeting anti-viral DExD-box RNA helicases. Overall, our findings indicate that various DExD-box RNA helicases serve as either pro- and/or anti-viral agents across a wide range of viruses. Continued investigation into the pro-viral activities of these helicases will help identify specific protein motifs that can be targeted by drugs to manage or eliminate the severe diseases caused by these viruses. Comparative studies on anti-viral DExD-box RNA helicase responses may also offer insights for developing therapies that enhance immune responses triggered by these helicases.

Organismal complexity strongly correlates with the number of protein families and domains

In the pregenomic era, scientists were puzzled by the observation that haploid genome size (the C-value) did not correlate well with organismal complexity. This phenomenon, called the "C-value paradox," is mostly explained by the fact that protein-coding genes occupy only a small fraction of eukaryotic genomes. When the first genome sequences became available, scientists were even more surprised by the fact that the number of genes (G-value) was also a poor predictor of complexity, which gave rise to the "G-value paradox." The proposed explanations usually invoke mechanisms that increase the information content of each individual gene (protein-protein interactions, intrinsic disorder, posttranslational modifications, alternative splicing, etc.). Less attention has been paid to mechanisms that increase the amount of genetic material but do not increase (or not to the same extent) the amount of information encoded in the genome, such as gene duplication and domain shuffling. Proteins belonging to the same family and/or sharing the same domains often carry out similar or even redundant functions. We thus hypothesized that an organism's number of different protein families and domains should be suitable predictors of organismal complexity. In agreement with our hypothesis, we observed that the number of protein families, clans, domains, and motifs increases from simple to progressively more complex organisms. In addition, these metrics correlate with the number of cell types better than and independently of the number of protein-coding genes and several previously proposed predictors of organismal complexity. Our observations have the potential to represent a resolution to the G-value paradox.

Genome-wide identification of the Sec14 gene family and the response to salt and drought stress in soybean (Glycine max)

BackgroundThe Sec14 domain is an ancient lipid-binding domain that evolved from yeast Sec14p and performs complex lipid-mediated regulatory functions in subcellular organelles and intracellular traffic. The Sec14 family is characterized by a highly conserved Sec14 domain, and is ubiquitously expressed in all eukaryotic cells and has diverse functions. However, the number and characteristics of Sec14 homologous genes in soybean, as well as their potential roles, remain understudied.ResultsIn this study, we identified 77 Sec14 genes in the soybean genome that were unevenly distributed across 19 chromosomes. Based on the classification method used for Arabidopsis Sec14 members, GmSec14s can be categorized into three classes: GmPITP1 to GmPITP37, GmSFH1 to GmSFH25, and GmPATL1 to GmPATL15. Structural analysis of the GmSec14 genes revealed that the SFH subfamily contained more introns than the other subfamilies. A total of 10 conserved protein motifs were detected within GmSec14 proteins, with each subfamily possessing unique motifs. Two tandem duplications and 73 segmental duplications were identified among the GmSec14 genes. Additionally, a large number of cis-acting elements, particularly those related to plant hormones, were abundant in the promoter regions of the GmSec14 genes. Tissue expression analysis of the GmSec14 genes indicated that they exhibited distinct tissue-specific expression patterns. In response to salt stress, multiple genes were found to be either upregulated or downregulated. In contrast, the majority of genes were downregulated under drought stress conditions. Notably, 12 GmSec14 genes exhibited significant alterations in expression following salt or drought stress, suggesting a potential role for these genes in stress response mechanisms. Furthermore, the protein interaction network and miRNA regulation associated with GmSec14s were predicted to elucidate the potential functions of GmSec14 members.ConclusionsThis study provides a systematic and comprehensive examination of the Sec14 gene family in soybean, which will facilitate further functional research into their roles in response to salt and drought tolerance.

Transcriptome-wide alternative mRNA splicing analysis reveals post-transcriptional regulation of neuronal differentiation.

Alternative splicing (AS) plays an important role in neuronal development, function, and disease. Efforts to analyze the transcriptome of AS inneurons on a wide scale are currently limited. We characterized the transcriptome-wide AS changes in SH-SY5Y neuronal differentiation model, which is widely used to study neuronal function and disorders. Our analysis revealed global changes in five AS programs that drive neuronal differentiation. Motif analysis revealed the contribution of RNA-binding proteins (RBPs) to the regulation of AS during neuronal development. We concentrated on the primary alternative splicing program that occurs during differentiation, specifically on events involving exon skipping (SE). Motif analysis revealed motifs for polypyrimidine tract-binding protein 1 (PTB) and ELAV-like RNA binding protein 1 (HuR/ELAVL1) to be the top enriched in SE events, and their protein levels were downregulated after differentiation. shRNA knockdown of either PTB and HuR was associated with enhanced neuronal differentiation and transcriptome-wide exon skipping events that drive the process of differentiation. At the level of gene expression, we observed only modest changes, indicating predominant post-transcriptional effects of PTB and HuR. We also observed that both RBPs altered cellular responses to oxidative stress, in line with the differentiated phenotype observed after either gene knockdown. Our work characterizes the AS changes in a widely used and important model of neuronal development and neuroscience research and reveals intricate post-transcriptional regulation of neuronal differentiation.

In situ NMR reveals a pH sensor motif in an outer membrane protein that drives bacterial vesicle production.

This work sheds light on the mechanism for extracellular vesicle biogenesis by Gram negative bacteria. It shows that the Salmonella surface protein PagC, a major driver of extracellular vesicle formation, harbors a set of pH-sensitive histidines that become protonated at acidic pH, increasing vesicle production, and promoting bacterial cell aggregation. NMR analysis of PagC in natively secreted bacterial vesicles is introduced as a new important tool for in situ structural analysis of bacterial membrane proteins. The results have important implications for understanding the molecular factors that drive the formation of bacterial extracellular vesicles, their functions in human infection, as well as their roles as vaccine, drug delivery and nanotechnology platforms.

Genome-Wide Identification and Analysis of Carbohydrate-Binding Modules in Colletotrichum graminicola

Colletotrichum graminicola is the causative agent of both maize stem rot and leaf blight, which are among the most damaging diseases affecting maize. Carbohydrate-binding modules (CBMs) are protein domains that lack catalytic activity and are commonly found alongside carbohydrate-hydrolyzing enzymes in fungi. A comprehensive examination of the C. graminicola TZ-3 genome resulted in the identification of 83 C. graminicola CBM (CgCBM) genes, which are characterized by distinct gene structures and protein motifs. Subcellular localization analysis revealed that the majority of CgCBM proteins were localized in the extracellular space. Investigation of the promoter regions of CgCBM genes uncovered a variety of responsive elements associated with plant hormones, including abscisic acid and methyl jasmonate response elements, as well as various stress-related response elements for drought, cold, defense, and other stress factors. Gene ontology analysis identified the primary functions of CgCBM genes as being linked to polysaccharide metabolism processes. Furthermore, the 83 CgCBM genes exhibited varying responses at different time points during C. graminicola infection, indicating their contribution to the fungus–maize interaction and their potential roles in the fungal pathogenic process. This study provides essential insights into CgCBMs, establishing a crucial foundation for further exploration of their functions in the mechanisms of fungal pathogenicity.

A novel NLP-based method and algorithm to discover RNA-binding protein (RBP) motifs, contexts, binding preferences, and interactions.

RNA-binding proteins (RBPs) are essential modulators in the regulation of mRNA processing. The binding patterns, interactions, and functions of most RBPs are not well-characterized. Previous studies have shown that motif context is an important contributor to RBP binding specificity, but its precise role remains unclear. Despite recent computational advances to predict RBP binding, existing methods are challenging to interpret and largely lack a categorical focus on RBP motif contexts and RBP-RBP interactions. There remains a need for interpretable predictive models to disambiguate the contextual determinants of RBP binding specificity in vivo . Here, we present a novel and comprehensive pipeline to address these knowledge gaps. We devise a Natural Language Processing-based decomposition method to deconstruct sequences into entities consisting of a central target k -mer and its flanking regions, then use this representation to formulate the RBP binding prediction task as a weakly supervised Multiple Instance Learning problem. To interpret our predictions, we introduce a deterministic motif discovery algorithm designed to handle our data structure, recapitulating the established motifs of numerous RBPs as validation. Importantly, we characterize the binding motifs and binding contexts for 71 RBPs, with many of them being novel. Finally, through feature integration, transitive inference, and a new cross-prediction approach, we propose novel cooperative and competitive RBP-RBP interaction partners and hypothesize their potential regulatory functions. In summary, we present a complete computational strategy for investigating the contextual determinants of specific RBP binding, and we demonstrate the significance of our findings in delineating RBP binding patterns, interactions, and functions.

Genome-wide identification and expression analysis of the SIRT gene family in Nile tilapia (Oreochromis niloticus).

The sirtuin (SIRT) family is a nicotine adenine dinucleotide (NAD+)-dependent class III histone deacetylase, which is widely involved in numerous physiological processes of organisms, such as metabolism, reproduction, and immunity. Here, based on the genomics database, comprehensive analysis of the SIRT gene in Nile tilapia (Oreochromis niloticus) was analyzed using bioinformatics methods and quantitative real-time PCR. The nine SIRT genes of O. niloticus (OnSIRT) were distributed on eight chromosomes. The OnSIRTs contain distinct sequences from 3 exons in OnSIRT4 to 16 exons in OnSIRT2, however, they share conserved domains and protein motifs. Phylogenetic analysis shows that the OnSIRTs belong to four subfamilies and are highly conserved in teleosts, and evolution is characterized primarily by purification selection. The OnSIRT genes showed diversified expression patterns in fourteen tissues of O. niloticus. OnSIRT2, OnSIRT3, OnSIRT3.2, OnSIRT6, and OnSIRT7 are mainly expressed in the gonads, especially in the ovary. OnSIRT1 and OnSIRT4 are mainly expressed in the kidney. OnSIRT5a is mainly expressed in the stomach, however, OnSIRT5b is mainly expressed in the liver and spleen. The results of this study provide a basis information for further exploration of the function and molecular mechanism of the SIRT gene family in teleosts.

Genome-Wide Identification and Characterization of the Homeodomain Leucine Zipper Protein (HD-Zip) Gene Family in Sea Buckthorn (Hippophae rhamnoides) Under Lead Stress

This study investigates the role of sea buckthorn HD-Zip genes in response to lead stress, identifying 28 genes distributed across 10 chromosomes, which are classified into four subfamilies. Each subfamily exhibits a similar gene structure and conserved protein motifs. The HD-Zip gene family is notably enriched in stress-responsive elements. Transcriptomic analysis revealed differential expression among the 28 members of the HD-Zip gene family in sea buckthorn, varying with different Pb ion concentrations. Upregulated genes were predominantly observed at stress concentrations of 1 g/kg and 5 g/kg, while downregulated genes were more prevalent at the 0.5 g/kg stress concentration. Covariance analysis indicated that large-scale gene duplication was the primary mechanism driving the expansion of the sea buckthorn HD-Zip gene family. Additionally, analysis of three-dimensional protein structures demonstrated high conservation within the HD-Zip gene, suggesting that certain sea buckthorn HD-Zip proteins may play significant regulatory roles in physiological functions. Scanning electron microscopy–energy-dispersive spectroscopy (SEM-EDS) analysis revealed that the majority of lead ions accumulated in the roots of the seedlings, with the lead concentration affecting the number, density, and function of leaf slits. These findings enhance our understanding of the complex regulatory mechanisms governing HD-Zip genes and will contribute to the genetic improvement of sea buckthorn for breeding under lead stress conditions.

Design of a TSR-based project learning strategy for biochemistry undergraduate teaching and research labs: a case study

Given the exponential growth of biochemical data and deep effect of computational methods on life sciences, there is a need to rethink undergraduate curricula. A project-oriented learning approach based on the Triangular Spatial Relationship (TSR) algorithm has been developed. The TSR-based method was designed for protein 3D structural comparison, motif discovery and probing molecular interactions. The uniqueness of the method benefits students’ learning of big data and computational methods. Specifically, students learn (i) how to search proteins of interest from the PDB archive, (ii) basic supercomputer skills, (iii) how to prepare datasets, (iv) how to perform protein structure and sequence analyses, (v) how to interpret the results, visualize protein structures and make graphs. Five specific strategies have been developed to achieve students’ highest potentials. (i) This lab exercise is designed as a project-oriented learning approach. (ii) The skills-first and concept-second approach is used. (iii) Students choose the proteins based on their interests. (iv) Students are encouraged to learn from each other to promote student–student interactions. (v) Students are required to write a report and/or present their studies. To assess students’ performance, we have developed an assessment rubric that includes (i) demonstration of supercomputer skills in job script preparation, submission and monitoring, (ii) skills in preparation of datasets, (iii) data analytical skills, (iv) project report, (v) presentation, and (vi) integration of the TSR-based method with other computational methods (e.g., molecular 3D structural visualization and protein sequence analysis). This project has been introduced in undergraduate biochemistry research and teaching labs for 4 years. Most students have learned the basic supercomputer skills as well as structure data analysis skills. Students’ feedback is positive and encouraging. It can be further developed as a module for an integrated computational chemistry lecture course.

Systematic characterization of the bZIP gene family in Colletotrichum siamense and functional analysis of three family members

The basic leucine zipper (bZIP) transcription factors (TFs) play important roles in many physiological processes of plant-pathogenic fungi, especially concerning fungal development, fungicide resistance, and pathogenicity. Colletotrichum siamense is the predominant species causing Colletotrichum leaf disease (CLD) in rubber trees. However, little is known about the bZIP genes in C. siamense. In this study, 25 bZIP genes were systematically identified in the genome of C. siamense, and molecular features were characterized. Evolutionarily, the CsbZIP genes were divided into 11 groups, with the members in the same group sharing similar gene structures and conserved protein motif organizations. Furthermore, protein-protein interaction (PPI) analysis revealed that 15 bZIP proteins had functional partners in common or interacted with other CsbZIP proteins. Additionally, the expression of 23 CsbZIP genes changed in response to the antifungal chemicals melatonin, prochloraz, and thymol, and the genes could be divided into three clusters based on their expression patterns. Finally, gene deletion mutants of CsbZIP01/09/17 were constructed and functional analysis indicated that these genes operated as important regulators of mycelial growth, fungicide resistance, ergosterol biosynthesis, and virulence in C. siamense. This study provided the foundations crucial for further investigation of the functions of CsbZIP TFs in fungicide resistance and virulence.

PiRNA processing within non-membrane structures is governed by constituent proteins and their functional motifs.

Discovered two decades ago, PIWI-interacting RNAs (piRNAs) are crucial for silencing transposable elements (TEs) in animal gonads, thereby protecting the germline genome from harmful transposition, and ensuring species continuity. Silencing of TEs is achieved through transcriptional and post-transcriptional suppression by piRNAs and the PIWI clade of Argonaute proteins within non-membrane structured organelle. These structures are composed of proteins involved in piRNA processing, including PIWIs and other proteins by distinct functional motifs such as the Tudor domain, LOTUS, and intrinsic disordered regions (IDRs). This review highlights recent advances in understanding the roles of these conserved proteins and structural motifs in piRNA biogenesis. We explore the molecular mechanisms of piRNA biogenesis, with a primary focus on Drosophila as a model organism, identifying common themes and species-specific variations. Additionally, we extend the discussion to the roles of these components in nongonadal tissues.