陆地棉GhIQD基因家族的鉴定及表达分析

窦玲玲^1?, 吕丽敏^2?, 康洋洋¹, 田瑞洁¹, 黄得青¹, 李佳茵¹, 李思懿¹, 刘凤萍¹, 曹凌燕¹, 金玉花¹, 刘洋¹, 李怀珠¹, 王文博¹, 庞朝友², 商海红^2,3, 邹长松⁴, 宋国立^2,3*, 肖光辉^3,5*,

1.咸阳师范学院化学与化工学院，咸阳712000；2.中国农业科学院棉花研究所/棉花生物学国家重点实验室，安阳455000；3.棉花生物学国家重点实验室郑州大学研究基地，郑州 450000；4.河南大学生命科学学院/植物逆境生物学重点实验室/棉花生物学国家重点实验室，开封 475000；5陕西师范大学生命科学学院，西安710119

 (^?并列一作，*通信作者)

背景：钙调素（Calmodulin, CaM）是植物中最重要的钙离子信号受体之一，调节植物的多种生理生化反应。钙调素通过与钙调素结合蛋白（CaM-binding proteins, CaMBPs）结合来调节Ca²⁺信号转导。IQ domain（IQD）蛋白是植物特异性的钙调素结合蛋白，通过特定的钙调素结合位点与CaM结合参与调控植物的生长发育。

结果：本研究从陆地棉基因组中共鉴定出102个GhIQD基因，并将其分为4个亚组（I、II、III和IV）。基因复制分析表明，102个GhIQD基因中有100个是由片段重复引起的，由此推断片段重复是GhIQD基因扩展的主要方式。基因表达谱分析表明，共有89个GhIQD基因在棉纤维伸长期和次级细胞壁合成期表达，因此推断GhIQD基因参与了棉花纤维的生长发育。对20个GhIQD基因进行荧光定量表达分析发现，这些基因在棉花各种组织中均高调表达，且能被MeJA诱导表达。
结论：我们的研究表明GhIQD基因参与棉纤维发育，并能被MeJA广泛诱导。该研究系统分析了GhIQD基因的进化和棉纤维发育进行了分析，为进一步分析其在棉纤维发育中的作用奠定了基础。

Background

Calmodulin (CaM) is one of the most important Ca²⁺ signaling receptors because it regulates diverse physiological and biochemical reactions in plants. CaM functions by interacting with CaM-binding proteins (CaMBPs) to modulate Ca²⁺ signaling. IQ domain (IQD) proteins are plant-specific CaMBPs that bind to CaM by their specific CaM binding sites.

Results

In this study, we identified 102 GhIQD genes in the Gossypium hirsutum L. genome. The GhIQD gene family was classified into four clusters (I, II, III, and IV), and we then mapped the GhIQD genes to the G. hirsutum L. chromosomes. Moreover, we found that 100 of the 102 GhIQD genes resulted from segmental duplication events, indicating that segmental duplication is the main force driving GhIQD gene expansion. Gene expression pattern analysis showed that a total of 89 GhIQD genes expressed in the elongation stage and second cell wall biosynthesis stage of the fiber cells, suggesting that GhIQD genes may contribute to fiber cell development in cotton. In addition, we found that 20 selected GhIQD genes were highly expressed in various tissues. Exogenous application of MeJA significantly enhanced the expression levels of GhIQD genes.

Conclusions

Our study shows that GhIQD genes are involved in fiber cell development in cotton and are also widely induced by MeJA. Thw results provide bases to systematically characterize the evolution and biological functions of GhIQD genes, as well as clues to breed better cotton varieties in the future.

Title: Genome-wide identification and expression analysis of the GhIQD gene family in upland cotton (Gossypium hirsutum L.)

Authors: DOU Lingling, LV Limin, KANG Yangyang, TIAN Ruijie, HUANG Deqing, LI Jiayin, LI Siyi, LIU Fengping, CAO Lingyan, JIN Yuhua, LIU Yang, LI Huaizhu, WANG Wenbo, PANG Chaoyou, SHANG Haihong, ZOU Changsong, SONG Guoli & XIAO Guanghui

Journal of Cotton Research. 2021, 4: 4

https://doi.org/10.1186/s42397-021-00079-3

https://jcottonres.biomedcentral.com/articles/10.1186/s42397-021-00079-3