Genome-wide Identification and Evolution of the PP2C Gene Family in Eight Rosaceae Species and Expression Analysis Under Stress in Pyrus bretschneideri.

Guoming Wang,Xun Sun,Zhihua Guo,Shaoling Zhang,Lei Guo,Dirk Joldersma,Chao Gu,Xin Qiao,Kaijie Qi

doi:10.3389/fgene.2021.770014

Abstract

Type 2C protein phosphatase (PP2C) plays an essential role in abscisic acid (ABA) signaling transduction processes. In the current study, we identify 719 putative PP2C genes in eight Rosaceae species, including 118 in Chinese white pear, 110 in European pear, 73 in Japanese apricot, 128 in apple, 74 in peach, 65 in strawberry, 78 in sweet cherry, and 73 in black raspberry. Further, the phylogenetic analysis categorized PbrPP2C genes of Chinese white pear into twelve subgroups based on the phylogenic analysis. We observed that whole-genome duplication (WGD) and dispersed gene duplication (DSD) have expanded the Rosaceae PP2C family despite simultaneous purifying selection. Expression analysis finds that PbrPP2C genes have organ-specific functions. QRT-PCR validation of nine PbrPP2C genes of subgroup A indicates a role in ABA-mediated response to abiotic stress. Finally, we find that five PbrPP2C genes of subgroup A function in the nucleus. In summary, our research suggests that the PP2C family functions to modulate ABA signals and responds to abiotic stress.

Highlights

Protein phosphorylation is a fundamental signal that regulates cellular processes, including growth factor responses, hormone responses, metabolic control, and developmental processes, and as with all signals, removal is as important as induction
A total of 719 putative type 2C protein phosphatase (PP2C) genes were identified in eight Rosaceae species: 118 in Chinese white pear, 110 in European pear, 73 in Japanese apricot, 128 in apple, 74 in peach, 65 in strawberry (Haider et al, 2019), 78 in sweet cherry, and 73 in black raspberry (Supplementary Table S1). 118 putative PP2C genes of pear were arranged as PbrPP2C1 to PbrPP2C118 based on phylogenic analysis and the relative position of Arabidopsis orthologs
Splicing variants played a crucial role in the posttranscriptional regulatory mechanism that modulates transcriptome and proteome diversity, such as alternative splicing of PpDAM1 was important in the pear flower bud dormancy process (Li et al, 2021)

Summary

Introduction

Protein phosphorylation is a fundamental signal that regulates cellular processes, including growth factor responses, hormone responses, metabolic control, and developmental processes, and as with all signals, removal is as important as induction (den Hertog 1999; Kerk et al, 2002; Schweighofer et al, 2007). Protein kinases (PKs) phosphorylate serine (Ser), threonine (Thr), and tyrosine (Tyr). The PPs are classified into three groups based on substrate specificity: protein Tyr phosphatases (PTPs), Ser/Thr phosphatases (STPs), and dual-specificity phosphatases (DSPTPs) (Cohen, 1989; Kerk et al, 2008). STPs are further divided into three subgroups: the phosphor-protein phosphatase (PPP), Mg2+- or Mn2+-dependent protein phosphatase (PPM), and aspartate-based protein phosphatases (Cohen 1989; Kerk et al, 2008). The PPP family covers PP1, PP2A, PP4, PP5, PP6, PP7, and PP2B, whereas the PPM family includes type 2C protein phosphatases (PP2Cs) and pyruvate dehydrogenase phosphatases (Cohen, 1989; Kerk et al, 2008)

Methods

Results

Discussion

Conclusion