Transcript structure and domain display: a customizable transcript visualization tool

VisProDom: an interactive Shiny/R application for displaying protein domains with transcriptional features

Background

Both the protein domains and transcript structures influence protein functional variation. The genomic location of both protein domains and transcript structural features can be described using the genomic coordinates of their encoded sequences. However, the coordinates of protein domains and transcriptional features often differ greatly, and it is difficult to view them in combination at the genome-wide level. In this paper, we describe the development of a new tool that allows users to visualize domains and transcript features together, using either built-in or uploaded genome datasets, and export publication-ready figures. 

Results

We developed a user-friendly, independent R package and Shiny web application named “VisProDom”. VisProDom consists of a genome-wide database containing entire annotated transcripts merged with annotated protein domains from the Pfam database. The built-in dataset includes 82 files, which merge genome general feature format (GFF) annotations with rpsblast tabular outputs from protein sequence searches in the Pfam database. Multiple genomes can be simultaneously screened for protein domains or transcript names. VisProDom includes step-by-step introductions and clickable elements for ease of use.

Conclusion

VisProDom can display hundreds of transcripts alongside protein domains and export figures in a publication-ready format. This makes it a valuable tool for molecular evolution and comparative genomics.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08713-3.

Dynamic differential evolution schemes of WRKY transcription factors in domesticated and wild rice

WRKY transcription factors play key roles in stress responses, growth, and development. We previously reported on the evolution of WRKYs from unicellular green algae to land plants. To address recent evolution events, we studied three domesticated and eight wild species in the genus Oryza, an ideal model due to its long history of domestication, economic importance, and central role as a model system. We have identified prevalence of Group III WRKYs despite differences in breeding of cultivated and wild species. Same groups of WRKY genes tend to cluster together, suggesting recent, multiple duplication events. Duplications followed by divergence may result in neofunctionalizations of co-expressed WRKY genes that finely tune the regulation of target genes in a same metabolic or response pathway. WRKY genes have undergone recent rearrangements to form novel genes. Group Ib WRKYs, unique to AA genome type Oryza species, are derived from Group III genes dated back to 6.76 million years ago. Gene tree reconciliation analysis with the species tree revealed details of duplication and loss events in the 11 genomes. Selection analysis on single copy orthologs reveals the highly conserved nature of the WRKY domain and clusters of fast evolving sites under strong positive selection pressure. Also, the numbers of single copy orthologs under positive or negative selection almost evenly split. Our results provide valuable insights into the preservation and diversification of an important gene family under strong selective pressure for biotechnological improvements of the world's most valued food crop.

WRKY transcription factor genes in wild rice Oryza nivara

The WRKY transcription factor family is one of the largest gene families involved in plant development and stress response. Although many WRKY genes have been studied in cultivated rice (Oryza sativa), the WRKY genes in the wild rice species Oryza nivara, the direct progenitor of O. sativa, have not been studied. O. nivara shows abundant genetic diversity and elite drought and disease resistance features. Herein, a total of 97 O. nivara WRKY (OnWRKY) genes were identified. RNA-sequencing demonstrates that OnWRKY genes were generally expressed at higher levels in the roots of 30-day-old plants. Bioinformatic analyses suggest that most of OnWRKY genes could be induced by salicylic acid, abscisic acid, and drought. Abundant potential MAPK phosphorylation sites in OnWRKYs suggest that activities of most OnWRKYs can be regulated by phosphorylation. Phylogenetic analyses of OnWRKYs support a novel hypothesis that ancient group IIc OnWRKYs were the original ancestors of only some group IIc and group III WRKYs. The analyses also offer strong support that group IIc OnWRKYs containing the HVE sequence in their zinc finger motifs were derived from group Ia WRKYs. This study provides a solid foundation for the study of the evolution and functions of WRKY genes in O. nivara.