Genome-Wide Analyses of the NAC Transcription Factor Gene Family in Pepper (Capsicum annuum L.): Chromosome Location, Phylogeny, Structure, Expression Patterns, Cis-Elements in the Promoter, and Interaction Network.

The NAM, ATAF1/2, and CUC2 (NAC) transcription factors form a large plant-specific gene family, which is involved in the regulation of tissue development in response to biotic and abiotic stress. To date, there have been no comprehensive studies investigating chromosomal location, gene structure, gene phylogeny, conserved motifs, or gene expression of NAC in pepper ( L.). The recent release of the complete genome sequence of pepper allowed us to perform a genome-wide investigation of L. NAC () proteins. In the present study, a comprehensive analysis of the gene family in pepper was performed, and a total of 104 genes were identified. Genome mapping analysis revealed that genes were enriched on four chromosomes (chromosomes 1, 2, 3, and 6). In addition, phylogenetic analysis of the NAC domains from pepper, potato, , and rice showed that genes could be clustered into three groups (I, II, and III). Group III, which contained 24 genes, was exclusive to the plant family. Gene structure and protein motif analyses showed that these genes were relatively conserved within each subgroup. The number of introns in genes varied from 0 to 8, with 83 (78.9%) of genes containing two or less introns. Promoter analysis confirmed that genes are involved in pepper growth, development, and biotic or abiotic stress responses. Further, the expression of 22 selected genes in response to seven different biotic and abiotic stresses [salt, heat shock, drought, , abscisic acid, salicylic acid (SA), and methyl jasmonate (MeJA)] was evaluated by quantitative RT-PCR to determine their stress-related expression patterns. Several putative stress-responsive genes, including 72 and 27, which are orthologs of the known stress-responsive gene 055 and potato gene 30, respectively, were highly regulated by treatment with different types of stress. Our results also showed that 36 plays an important role in the interaction network, interacting with 48 genes. Most of these genes are in the mitogen-activated protein kinase (MAPK) family. Taken together, our results provide a platform for further studies to identify the biological functions of genes.

Diao W ，Snyder JC ，Wang S ，Liu J ，Pan B ，Guo G ，Ge W ，Dawood MHSA ... -  《INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES》

Genome-wide analysis, expression profile of heat shock factor gene family (CaHsfs) and characterisation of CaHsfA2 in pepper (Capsicum annuum L.).

Guo M ，Lu JP ，Zhai YF ，Chai WG ，Gong ZH ，Lu MH ... -  《BMC PLANT BIOLOGY》

Identification of CBL and CIPK gene families and functional characterization of CaCIPK1 under Phytophthora capsici in pepper (Capsicum annuum L.).

Ma X ，Gai WX ，Qiao YM ，Ali M ，Wei AM ，Luo DX ，Li QH ，Gong ZH ... -  《BMC GENOMICS》

Characterization of the GGP gene family in potato (Solanum tuberosum L.) and Pepper (Capsicum annuum L.) and its expression analysis under hormonal and abiotic stresses.

GDP-L-galactose phosphorylase (GGP) is a key rate-limiting enzyme in plant ascorbic acid synthesis, which plays an important role in plant growth and development as well as stress response. However, the presence of GGP and its function in potato and pepper are not known. In this study, we first identified two GGP genes in each potato and pepper genomes using a genome-wide search approach. We then analyzed their physicochemical properties, conserved domains, protein structures and phylogenetic relationships. Phylogenetic tree analysis revealed that members of the potato and pepper GGP gene families are related to eggplant (Solanum melongena L.), Arabidopsis (Arabidopsis thaliana L.), tobacco (Nicotiana tabacum L.) and tomato (Solanum lycopersicum L.), with tomato being the most closely related. The promoter sequences mainly contain homeopathic elements such as light-responsive, hormone-responsive and stress-responsive, with light-responsive elements being the most abundant. By analyzing the structure of the genes, it was found that there is no transmembrane structure or signal peptide in the GGP gene family of potatoes and peppers, and that all of its members are hydrophilic proteins. The expression profiles of different tissues show that StGGP1 has the highest expression levels in leaves, StGGP2 has the highest expression levels in stamens, and CaGGPs have the highest expression levels in the early stages of fruit development (Dev1). It was found that StGGPs and CaGGPs genes showed different response to phytohormones and abiotic stresses. Abscisic acid (ABA) treatment induced the most significant change in the expression of StGGPs, while the expression of CaGGPs showed the most pronounced change under methyl jasmonate (MeJA) treatment. StGGPs responded mainly to dark treatment, whereas CaGGPs responded mainly to NaCl stress. These results provide an important basis for a detailed study about the functions of GGP homologous genes in potato and pepper in response to abiotic stresses.

Ding Z ，Yao K ，Yao Y ，Pan X ，Luo L ，Li L ，Wang C ，Liao W ... -  《Scientific Reports》

Knockdown of CaHSP60-6 confers enhanced sensitivity to heat stress in pepper (Capsicum annuum L.).

Haq SU ，Khan A ，Ali M ，Gai WX ，Zhang HX ，Yu QH ，Yang SB ，Wei AM ，Gong ZH ... -  《-》