Genome wide identification and functional assignments of C2H2 Zinc-finger family transcription factors in Dichanthelium oligosanthes.

Raj Kumar Joshi

doi:10.6026/97320630015689

Abstract

Transcription factors (TFs) are biological regulators of gene function in response to various internal and external stimuli. C2H2 zinc finger proteins (C2H2-ZFPs) are a large family of TFs that play crucial roles in plant growth and development, hormone signalling and response to biotic and abiotic stresses. While C2H2-ZFPs have been well characterized in many model and crop plants, they are yet to be ascertained in the evolutionarily important C3 plant Dichanthelium oligosanthes (Heller's rosette grass). In the present study, we report 32 C2H2-ZF genes (DoZFs) belonging to three different classes-Q type, C-type and Z-type based on structural elucidation and phylogenetic analysis. Sequence comparisons revealed paralogs within the DoZFs and orthologs among with rice ZF genes. Motif assignment showed the presence of the distinctive C2H2-ZF conserved domain "QALGGH" in these proteins. Cis-element analysis indicated that majority of the predicted C2H2-ZFPs are associated with hormone signalling and abiotic stress responses. Further, their role in nucleic acid binding and transcriptional regulation was also observed using predicted functional assignment. Thus, we report an overview of the C2H2-ZF gene family in D. oligosanthes that could serve as the basis for future experimental studies on isolation and functional implication of these genes in different biological mechanism of C3 plants.

Highlights

Transcription factors (TFs) are regulatory proteins which play critical role in altering the expression of genes associated with multiple cellular pathways related to growth, development and stress responses [1]
Results & Discussion The HMM profile of the C2H2-ZF domain (PF00096) was used as a query to search for C2H2-ZF genes of D. oligosanthes within the protein databases using HMMER software
Subcellular localization using mGOASVM revealed that all except one C2H2ZFPs were predicted as nuclear proteins while only DoZFP4 was located in the endoplasmic reticulum

Summary

Introduction

Transcription factors (TFs) are regulatory proteins which play critical role in altering the expression of genes associated with multiple cellular pathways related to growth, development and stress responses [1]. Among the various TFs, the Zinc-finger proteins (ZFPs) are the largest group of transcription regulators in plants [2]. Since the discovery of the first ZFP from Petunia, several zinc-finger TFs have been identified from myraids of plants and their involvement in different biological processes including growth, development, reproduction, photosynthesis and stress responses have been reported [2]. Among all the ZFP types, C2H2-ZFPs are the most widely distributed transcription factors in eukaryotes. These are characterized by the presence of a conserved motif X2-Cys-X2–4-CysX12-His-X3–5-His, where X represents the amino acids that act as the spacer between the cysteine and the histidine residues [3]. Experimental analyses have shown that C2H2-ZFPs are represented by 3% of all genes in mammals, 2.3% of all the genes in Drosophila and 0.8% of all genes in yeast [4].Compared to other eukaryotes, the ISSN 0973-2063 (online) 0973-8894 (print)

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Results

Conclusion