Institute of Grain and Oil Crops, Yantai Academy of Agricultural Sciences, Yantai, 265500, China.
Key Laboratory of Sweet Potato Biology and Biotechnology, Ministry of Agriculture and Rural Affairs/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis & Utilization and Joint Laboratory for International Cooperation in Crop Molecular Breeding, Ministry of Education, College of Agronomy & Biotechnology, China Agricultural University, Beijing, 100193, China.
BMC Genomics. 2024 Jun 6;25(1):572. doi: 10.1186/s12864-024-10470-4.
KNOXs, a type of homeobox genes that encode atypical homeobox proteins, play an essential role in the regulation of growth and development, hormonal response, and abiotic stress in plants. However, the KNOX gene family has not been explored in sweet potato. In this study, through sequence alignment, genomic structure analysis, and phylogenetic characterization, 17, 12 and 11 KNOXs in sweet potato (I. batatas, 2n = 6x = 90) and its two diploid relatives I. trifida (2n = 2x = 30) and I. triloba (2n = 2x = 30) were identified. The protein physicochemical properties, chromosome localization, phylogenetic relationships, gene structure, protein interaction network, cis-elements of promoters, tissue-specific expression and expression patterns under hormone treatment and abiotic stresses of these 40 KNOX genes were systematically studied. IbKNOX4, -5, and - 6 were highly expressed in the leaves of the high-yield varieties Longshu9 and Xushu18. IbKNOX3 and IbKNOX8 in Class I were upregulated in initial storage roots compared to fibrous roots. IbKNOXs in Class M were specifically expressed in the stem tip and hardly expressed in other tissues. Moreover, IbKNOX2 and - 6, and their homologous genes were induced by PEG/mannitol and NaCl treatments. The results showed that KNOXs were involved in regulating growth and development, hormone crosstalk and abiotic stress responses between sweet potato and its two diploid relatives. This study provides a comparison of these KNOX genes in sweet potato and its two diploid relatives and a theoretical basis for functional studies.
KNOX 基因家族是一类编码典型同源异型盒蛋白的同源异型盒基因,在植物的生长发育、激素响应和非生物胁迫调控中发挥着重要作用。然而,甘薯中的 KNOX 基因家族尚未得到充分研究。在本研究中,通过序列比对、基因组结构分析和系统发育特征分析,在甘薯(Ipomoea batatas,2n=6x=90)及其两个二倍体近缘种 I.trifida(2n=2x=30)和 I.triloba(2n=2x=30)中鉴定到了 17、12 和 11 个 KNOX 基因。对这 40 个 KNOX 基因的蛋白理化性质、染色体定位、系统发育关系、基因结构、蛋白互作网络、启动子顺式作用元件、组织特异性表达以及激素和非生物胁迫处理下的表达模式进行了系统研究。IbKNOX4、-5 和 -6 在高产品种 Longshu9 和 Xushu18 的叶片中高度表达。I 类的 IbKNOX3 和 IbKNOX8 在初始储藏根中比纤维根上调表达。M 类的 IbKNOXs 在茎尖特异性表达,在其他组织中几乎不表达。此外,IbKNOX2 和 -6 及其同源基因受到 PEG/甘露醇和 NaCl 处理的诱导。结果表明,KNOX 基因参与调控甘薯与其两个二倍体近缘种之间的生长发育、激素交叉对话和非生物胁迫响应。本研究为甘薯及其两个二倍体近缘种的这些 KNOX 基因提供了比较,并为功能研究提供了理论依据。