Molecular Characterization of HSP20 and HSP40 Genes Governing Heat Stress Tolerance in Chili

Maliha Shah; Saman Khaliq; Mahek Batool Baig

doi:10.66432/mrq3xt08

Maliha Shah Department of Plant Breeding and Genetics, PMAS Arid Agriculture University Rawalpindi, Pakistan , Saman Khaliq * Department of Plant Breeding and Genetics, PMAS Arid Agriculture University Rawalpindi, Pakistan , Mahek Batool Baig Department of Plant Breeding and Genetics, PMAS Arid Agriculture University Rawalpindi, Pakistan

* Corresponding author: khaliqsaman98@gmail.com

DOI:

https://doi.org/10.66432/mrq3xt08

Keywords:

genome wide analysis, hsp 40 genes, HSP20 genes, heat shock proteins, heat stress, capsicum annum

Abstract

Heat stress has a devastating effect on the growth and development of plants as well as on their productivity, it leads to proteins destabilization and cellular homeostasis. The mitigation of these effects depends on heat shock proteins (HSPs). This paper gives a global identification, characterization and expression profiling of Hsp20 and Hsp40 families of genes in chili (Capsicum annuum) to understand their functions in heat stress tolerance. There were 64 non-redundant HSP20 genes found, mostly localized in the cytoplasm, then the nucleus, chloroplast and membrane additional findings provided support the hypothesis that HSP20 has a significant role in cytoplasmic protein protection. The structure of genes showed tight folds having a limited number of introns, which allows swift transcriptional stimulation during heat stress. Promoter analysis revealed that there are five high-profile cis-acting elements with ARRIA and WRKY71OS among them, which lend evidence to the belief that stress- and hormone-responsive signals play a complex role in the process of transcription. Genome wide screening of the HSP40 genes provided several cytoplasmic members which when expressed during heat shock indicates that they are involved in the activation of protective molecular chaperone complexes and the maintenance of cellular proteostasis. Hsp20 and Hsp40 proteins were found to coordinate their functions efficiently in stabilization of proteins and aggregation inhibition and maintaining metabolic continuity in the face of thermal stress. Altogether, the results offer useful molecular understanding of the thermotolerance processes in chili and discover candidate genes to molecular breeding and genetic engineering in improving heat stress tolerance in crops.

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