Comprehensive Workflow for the Genome-wide Identification and Expression Meta-analysis of the ATL E3 Ubiquitin Ligase Gene Family in Grapevine

Summary

This article describes the procedure for the identification and characterization of a gene family in grapevine applied to the family of Arabidopsis Tóxicos in Levadura (ATL) E3 ubiquitin ligases.

Abstract

Classification and nomenclature of genes in a family can significantly contribute to the description of the diversity of encoded proteins and to the prediction of family functions based on several features, such as the presence of sequence motifs or of particular sites for post-translational modification and the expression profile of family members in different conditions. This work describes a detailed protocol for gene family characterization. Here, the procedure is applied to the characterization of the Arabidopsis Tóxicos in Levadura (ATL) E3 ubiquitin ligase family in grapevine. The methods include the genome-wide identification of family members, the characterization of gene localization, structure, and duplication, the analysis of conserved protein motifs, the prediction of protein localization and phosphorylation sites as well as gene expression profiling across the family in different datasets. Such procedure, which could be extended to further analyses depending on experimental purposes, could be applied to any gene family in any plant species for which genomic data are available, and it provides valuable information to identify interesting candidates for functional studies, giving insights into the molecular mechanisms of plant adaptation to their environment.

Introduction

During the last decade, much research has been carried out in grapevine genomics. Grapevine is a recognized economically relevant crop, which has become a model for research on fruit development and on the responses of woody plants to biotic and abiotic stresses. In this context, the release of the Vitis vinifera cv. PN40024 genome in 2007¹ and its updated version in 2011² led to a rapid accumulation of "Omics"-scale data and to a burst of high-throughput studies. Based on the published sequence data, the comprehensive analysis of a given gene family (generally composed of proteins sharing conserved moti....

Protocol

1. Identification of Putative ATL Gene Family Member(s)

1. PSI-BLAST web version
   1. Open the BLAST web page¹³ and click on the protein BLAST section.
   2. In the "Enter Query sequence" field, enter the amino acid sequence of the protein (here VIT_05s0077g01970) that will be used as the probe to identify the other family members.
      NOTE: A good representative protein should be used (a protein displaying all the important features that characterize the family).
   3. In the field "Choose search set", select the "Reference protein" database (refseq_protein) and the organis....

Results

The VIT_05s0077g01970 gene, identified as the most similar to A. thaliana ATL2 (At3g16720) through a BLASTp search, was used as probe to survey the ATL family members in the grapevine genome (V. vinifera cv Pinot Noir PN40024). The PSI-BLAST analysis converged after a few cycles revealing a list of putative genes belonging to the grapevine ATL gene family (Figure 1A). The presence of the canonical RING-H2 domain for each candidate was evalua.......

Discussion

In the genomic era, many gene families have been deeply characterized in several plant species. This information is preliminary to functional studies and provide a frame to investigate further the role of different members in a family. In this context, there is also a need for a nomenclature system allowing to uniquely identify each member in a family, avoiding the redundancy and confusions that may arise when names are assigned independently to different genes by different research groups.

Af.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Personal computer
Basic Local Alignment Search Tool (BLAST)			https://blast.ncbi.nlm.nih.gov/Blast.cgi
Molecular Evolutionary Genetics Analysis (MEGA)			http://www.megasoftware.net/
Motif-based sequence analysis tools (MEME)			http://meme-suite.org/
Geneious	Biomatters Limited		http://www.geneious.com/
ProtParam Tool			http://web.expasy.org/protparam/
ngLOC			http://genome.unmc.edu/ngLOC/index.html
TargetP v1.1 Server			http://www.cbs.dtu.dk/services/TargetP/
Protein Prowler			http://bioinf.scmb.uq.edu.au:8080/pprowler_webapp_1-2/
MUsite			http://musite.sourceforge.net/
Pfam			http://pfam.xfam.org/
TMHMM Server v. 2.0			http://www.cbs.dtu.dk/services/TMHMM/
ProtScale			http://web.expasy.org/protscale/
Grape Genome Database (CRIBI)			http://genomes.cribi.unipd.it/grape/
PhenoGram			http://visualization.ritchielab.psu.edu/phenograms/plot
MCScanX			http://chibba.pgml.uga.edu/mcscan2/
Interactive Tree Of Life (iTOL)			http://itol.embl.de/
UniProt			http://www.uniprot.org/
Phylogeny.fr			http://www.phylogeny.fr/index.cgi
MUSCLE			http://www.ebi.ac.uk/Tools/msa/muscle/
Gblocks Server			http://molevol.cmima.csic.es/castresana/Gblocks_server.html
Vitis vinifera cv. Corvina gene expression Atlas datamatrix			https://www.researchgate.net/publication/273383414_54sample_ datamatrix_geneIDs_Fasoli2012
Multi Experiment Viewer (MeV)			http://mev.tm4.org/#/welcome
Sequence Read Archive (SRA)			https://www.ncbi.nlm.nih.gov/sra
R			https://www.r-project.org/
EMBOSS Needle (EMBL-EBI)			http://www.ebi.ac.uk/Tools/psa/emboss_needle/