Structural and functional characteristics and expression profile of the 20S proteasome gene family in Sorghum under abiotic stress

Vijai Malik; Faiza Mohamad Ikram; Yogita Singh; Vivek Kumar; Pranita Malik; Priyanka Balyan; Krishna Pal Singh; Reyazul Rouf Mir; Abeer Hashem; Graciela Dolores Avila-Quezada; Elsayed Fathi Abd Allah; Upendra Kumar

doi:10.3389/fpls.2023.1287950

Structural and functional characteristics and expression profile of the 20S proteasome gene family in Sorghum under abiotic stress

Front Plant Sci. 2023 Nov 29:14:1287950. doi: 10.3389/fpls.2023.1287950. eCollection 2023.

Authors

Affiliations

¹ Department of Botany, Chaudhary Charan Singh University, Meerut, India.
² Department of Molecular Biology & Biotechnology, College of Biotechnology, Chaudhary Charan Singh (CCS) Haryana Agricultural University, Hisar, India.
³ Department of Botany, Deva Nagri P.G. College, Chaudhary Charan Singh (CCS) University, Meerut, India.
⁴ Biophysics Unit, College of Basic Sciences & Humanities, Govind Ballabh (GB) Pant University of Agriculture & Technology, Pantnagar, India.
⁵ Mahatma Jyotiba Phule Rohilkhand University, Bareilly, India.
⁶ Division of Genetics and Plant Breeding, Sher-e-Kashmir University of Agricultural Sciences and Technology of Kashmir (SKUAST-Kashmir), Srinagar, India.
⁷ Botany and Microbiology Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
⁸ Facultad de Ciencias Agrotecnológicas, Universidad Autónoma de Chihuahua, Chihuahua, Chihuahua, Mexico.
⁹ Plant Production Department, College of Food and Agricultural Sciences, King Saud University, Riyadh, Saudi Arabia.
¹⁰ Department of Plant Science, Mahatma Jyotiba Phule Rohilkhand University, Bareilly, India.

^# Contributed equally.

Abstract

The 26S proteasome is a molecular machine that catalyzes and degrades protein intracellularly with the help of its core complex called 20S proteasome. The 20S proteasomes degrade and cleave denatured, cytotoxic, damaged, and unwanted proteins via proteolysis and impart biotic and abiotic stress tolerance in model plants. This study identified 20 genes, namely, 10 SbPA and 10 SbPB that encode for α- and β-subunits of the 20S proteasome in Sorghum bicolor (L.) Moench (2n= 20). These genes have been found distributed on the 1st, 2nd, 3rd, 4th, 5th, 7th, and 10th chromosomes. These sorghum genes were orthologous to corresponding rice. Phylogenetic analysis clustered these genes into seven clades, each with one of the seven α-subunits (1 to 7) and one of the seven β-subunits (1 to 7). In silico gene expression analysis suggested that nine genes were involved in abiotic stress response (cold, drought, and abscisic acid hormone). The expression of these proteasomal genes was studied in shoots and roots exposed to different abiotic stresses (cold, drought, and abscisic acid) by quantitative real-time polymerase chain reaction. A significant increase in the relative fold expression of SbPBA1, SbPAA1, SbPBG1, SbPBE1, and SbPAG1 genes under ABA and drought stress provides an insight into its involvement in abiotic stress. No expression was observed for cold stress of these genes indicating their non-involvement. It is believed that additional investigation into the SbPA/SbPB genes would aid in the creation of S. bicolor cultivars that are resistant to climate change.

Keywords: 20S proteasome gene family; Sorghum bicolor; cis-regulatory elements; gene duplication; homology modelling; miRNAs; splice variants.

Grants and funding

The author(s) declare that financial support was received for the research, authorship, and/or publication of this article. The authors are grateful to the UP state government [letter number 80/2021/1543 (1) sattar-4-2021-4(28)/10/8/2021] for providing fund for this research work. The authors would like to extend their sincere appreciation to the researchers supporting project number RSP2023R134, King Saud University, Riyadh, Saudi Arabia.