Genome-wide expression analysis of HSP70 family genes in rice and identification of a cytosolic HSP70 gene highly induced under heat stress

Abstract

The heat shock protein 70 (HSP70) gene family plays a key role in protecting plant cells or tissues from thermal or oxidative stress. Although many studies have elucidated the molecular functions of individual family members, genome-wide analysis of this family is still limited, especially for crop species. Our objective was to integrate various meta-profiling data into the context of a phylogenetic tree, which would enable us to perform fine evaluation of functional dominancy or redundancy within this family. Our data indicated that a loss-of-function mutant of a rice cytosolic HSP70 gene (OsctHSP70-1) did not show a clear defective phenotype in response to high temperature because of the existence of another gene family member that was closely clustered with OsctHSP70-1 and had similar expression patterns. Moreover, the second gene showed much stronger anatomical expression. We indirectly analyzed the function of OsctHSP70-1 by studying GUS activity under the control of the endogenous promoter. We also designed a probable interaction network mediated by OsctHSP70-1 and used co-expression analysis among its components to refine the network, suggesting more probable model to explain the function of OsctHSP70-1.

Genome-wide survey of heat shock factors and heat shock protein 70s and their regulatory network under abiotic stresses in Brachypodium distachyon

“…Our phylogenetics analysis with 32 rice, 18 Arabidopsis and 29 B . distachyon Hsp70 proteins revealed six subfamilies (Fig 3) [66]. Cluster I has 13 B .…”

Genome-wide identification of heat shock proteins (Hsps) and Hsp interactors in rice: Hsp70s as a case study

“…This finding was recently supported by Jung et al (2013). They found that the OsctHsp70-1 had a functional association with Ras/Raf-mediated MAPK kinase cascades [14]. …”

“…Rice is the most important staple food crop in the world and the principal model for other monocotyledonous species [10]. In recent years, researchers have made great efforts on the functional analysis of individual Hsp family members in rice [11–14], however Hsps still have not been fully characterized and little is known about their interactors [14]. …”

Comparative Expression Analysis of Rice and Arabidopsis Peroxiredoxin Genes Suggests Conserved or Diversified Roles Between the Two Species and Leads to the Identification of Tandemly Duplicated Rice Peroxiredoxin Genes Differentially Expressed in Seeds

“…We recently suggested putative functions for most members of several gene families based on the integration of experimental and meta-expression data (Jung et al 2013; Jin et al 2012; Nguyen et al 2013; Nguyen et al 2014; Nguyen et al 2015). Applying a similar approach with the rice PRX family could help elucidate the functions of those members.…”