Functional analysis of nine cotton genes related to leaf senescence in Gossypium hirsutum L

Abstract

Leaf senescence is defined as a deterioration process that continues to the final developmental stage of leaf. This process is usually regulated by both external and internal factors. There are about 5356 senescence associated genes belonging to 44 plant species. A great number of these genes were identified in Arabidopsis. Leaf senescence can be regulated by many transcription factors. In this study, nine gene families were selected according to their expression levels during leaf senescence from our laboratory database. Phylogenetic tree was constructed by MEGA6. Cultivated cotton CCRI-10 seeds were sown in the experimental field of Institute of Cotton Research of CAAS for profiling and leaf development stages analysis. For abiotic (drought and salt) stress and phytohormone (ABA, SA, ET and JA) treatments, CCRI-10 seeds were sown in potting soil at 25 °C in a chamber room. Total RNA was isolated from various samples and the cDNA prepared for qRT-PCR. The comparative CT method was applied to calculate the relative expression levels of genes. For phylogenetic tree, nine cotton genes were divided into two groups, most of homologous genes in previous studies showed roles in phytohormones and abiotic stress. Expression profiling of the nine genes showed different patterns of tissue specific expression. In leaf development stages, majority of cotton genes showed high expression in early and complete senescence stage. Furthermore, most of cotton genes have positive or negative response to phytohormones and abiotic stress. Based on the results of this study, we found four cotton genes CotAD_07559, CotAD_37422, CotAD_21204 and CotAD_54353 as candidate genes for leaves senescence and abiotic stress.

Transcription Factors Associated with Leaf Senescence in Crops

“…Besides, different TF families regulate leaf senescence in cotton. Elasad et al [190] reported nine cotton genes that increased their expression during leaf senescence, with CotAD_37422 as the only TF member of the GRF (ortholog to the AT4G37740.1 gene). Further analyses must be done to confirm the functionality of this TF in regulating leaf senescence [190].…”

Regulatory Network of Cotton Genes in Response to Salt, Drought and Wilt Diseases (Verticillium and Fusarium): Progress and Perspective

“…Gh_D06G0281 (DTX/MATE) overexpressing Arabidopsis improved tolerance to salt, drought, and cold stress with a high level of antioxidant enzyme production and significantly lower levels of oxidant ( Lu et al, 2019 ). Additionally, recent genome wide studies of PIN-FORMED ( PIN ), respiratory burst oxidase homolog ( Ghrboh ), Valine-glutamine ( VQ ) gene family, heat shock protein 20 (Hsp20), at-hook motif containing nuclear localized ( AHL ), leaf senescence, protein phosphatases (PP2C), 9-cisepoxycarotenoiddioxygenase (NCED), and Myo-inositol oxygenase (MIOX) have laid a foundation to predict the regulatory network of cotton genes in response to various abiotic stresses ( Ma et al, 2016 ; He et al, 2017 ; Elasad et al, 2018 ; Shazadee et al, 2019 ; Chen et al, 2020 ; Li Z. et al, 2020 ; Wang W. et al, 2020 ; Zhao et al, 2020 ; Li Q. et al, 2021 ). To gain a better understanding, we summarized the regulatory networks of cotton genes in response to salt and drought in this review ( Table 1 ).…”

Genome-Wide Identification, Characterization, and Expression Analysis of the NAC Gene Family in Litchi chinensis

“…Numerous studies have shown that NAC transcription factors are involved in the regulation of plant growth and development, resistance to stress, disease resistance, and hormone signaling [10,14]. Elasad et al discovered that the NAC transcription factor in cotton Gossypium positively regulates leaf senescence [15]. NAP is a member of the NAC family associated with senescence in Arabidopsis, and overexpression of the NAP gene resulted in early senescence, while the NAP mutant plants showed delayed senescence.…”