The Protein Disulfide Isomerase gene family in bread wheat (T. aestivum L.)

Abstract

BackgroundThe Protein Disulfide Isomerase (PDI) gene family encodes several PDI and PDI-like proteins containing thioredoxin domains and controlling diversified metabolic functions, including disulfide bond formation and isomerisation during protein folding. Genomic, cDNA and promoter sequences of the three homoeologous wheat genes encoding the "typical" PDI had been cloned and characterized in a previous work. The purpose of present research was the cloning and characterization of the complete set of genes encoding PDI and PDI like proteins in bread wheat (Triticum aestivum cv Chinese Spring) and the comparison of their sequence, structure and expression with homologous genes from other plant species.ResultsEight new non-homoeologous wheat genes were cloned and characterized. The nine PDI and PDI-like sequences of wheat were located in chromosome regions syntenic to those in rice and assigned to eight plant phylogenetic groups. The nine wheat genes differed in their sequences, genomic organization as well as in the domain composition and architecture of their deduced proteins; conversely each of them showed high structural conservation with genes from other plant species in the same phylogenetic group. The extensive quantitative RT-PCR analysis of the nine genes in a set of 23 wheat samples, including tissues and developmental stages, showed their constitutive, even though highly variable expression.ConclusionsThe nine wheat genes showed high diversity, while the members of each phylogenetic group were highly conserved even between taxonomically distant plant species like the moss Physcomitrella patens. Although constitutively expressed the nine wheat genes were characterized by different expression profiles reflecting their different genomic organization, protein domain architecture and probably promoter sequences; the high conservation among species indicated the ancient origin and diversification of the still evolving gene family. The comprehensive structural and expression characterization of the complete set of PDI and PDI-like wheat genes represents a basis for the functional characterization of this gene family in the hexaploid context of bread wheat.

Evolutionary Relationship of Wheat Protein Disulphide Isomerase (PDI) Gene Promoter Sequence Based on Phylogenetic Analysis

“…The comparison of typical PDI gene sequences of wheat, rice and Arabidopsis showed a significant conservation of the exon/intron structure across the three species [31]. More detailed study on the complexity and diversity of the genes encoding PDI and PDI-like proteins in wheat and other plant species also showed a significant conservation of the exon/intron structure [28].…”

“…It has been cloned and sequenced in many plant species, such as alfalfa [17], barley [18], maize [19], castor bean [20], soyabean [21][22][23][24], common and durum wheat [25,26]. A detailed knowledge of the complexity and diversity of the genes encoding PDI and PDI-like proteins in Arabidopsis thaliana, wheat and other plant species was described by [27,28].…”

Identification of proteins related to microspore embryogenesis responsiveness in anther cultures of winter triticale (×Triticosecale Wittm.)

“…PDIs are suggested to play a role as chaperones because of their ability to bind to unfolded or partially folded proteins (Wang and Tsou 1993). In cereals these proteins are important in multiple metabolic functions, including secretory protein folding and redox signalling (d'Aloisio et al 2010).…”

Signal transduction during wheat grain development

“…PDI-like proteins would also be involved in signal transduction pathways through their association with transcriptional complexes regulating genes responding to various stimuli. The most expressed genes TaPDIL1-1, TaPDIL2-1 and TaPDIL8-1 displayed divergent expression patterns during grain development (d'Aloisio et al 2010). Calmodulin is a Ca 2?…”