Phylogenetic analysis and expression profiles of jasmonate ZIM-domain gene family provide insight into abiotic stress resistance in sunflower

Abstract

Jasmonate ZIM-domain (JAZ) proteins act as inhibitory factors of the jasmonic acid (JA) pathway, which is involved in regulating plant development and defense responses. However, there are no extensive studies available on JAZ genes in sunflower (Helianthus annuus L.). In this study, the phylogenetic analysis of 139 putative JAZ genes from eight plants demonstrated that these JAZs could be divided into five groups (Groups I–V), and the 27 sunflower JAZs (HaJAZs) were classified into these five groups. All groups contained genes from both monocotyledons and dicotyledons, indicating that the emergence of JAZ genes predates the differentiation of monocotyledons and dicotyledons. Both segmental and tandem duplications contributed greatly to this gene family’s expansion in sunflower, especially in Group II. Moreover, the expression profiles of HaJAZ genes under normal conditions, hormone treatments or abiotic stresses were analyzed based on RNA-seq data. HaJAZ2 may be undergoing pseudogenization as a nonfunctional gene because it was not expressed in any tissue. Many HaJAZ genes in roots upregulated their expression when involved in responding to exogenous hormones, especially methyl-jasmonate. The abiotic stress treatments of sunflower showed that HaJAZ5, HaJAZ15, HaJAZ17, HaJAZ20, and HaJAZ21 tend to be sensitive to certain abiotic stresses. HaJAZs from different groups may share similar functions but also exercise their unique functions when responding to abiotic stresses. We speculated that this gene family was conserved in sequence but varied in its expression among duplicated HaJAZ genes, which implies that they may confer neofunctionalization in the adaptation to abiotic stresses; this work provides insight into the resistance of sunflowers and their adaptation to diverse environmental conditions.

Genome-wide identification and evolution of the SAP gene family in sunflower (Helianthus annuus L.) and expression analysis under salt and drought stress

“…The variation in exon‒intron numbers and conserved motifs within gene families often provides valuable insights into the evolutionary mechanisms of those gene families ( Abdullah-Zawawi et al, 2021 ; Song et al, 2022 ). In the investigation of SAP genes across seven Compositae species, it was observed that members of the same subfamily exhibited similar exon‒intron numbers and conserved motifs, suggesting shared biological functions within subfamilies.…”

Systematic analysis of Heat Shock Protein 70 (HSP70) gene family in radish and potential roles in stress tolerance

“…The exon–intron organizations and conserved motifs were visualized with TBtools (v1.108) [ 37 ]. The online PlantCARE database ( http://bioinformatics.psb.ugent.be/webtools/plantcare/html/ ) was used to determine the putative cis -acting regulatory elements, as described previously [ 38 ].…”