Isolation and expression pattern of COR15b and KIN1 genes in watermelon and pumpkin
Isolation and expression pattern of COR15b and KIN1 genes in watermelon and pumpkin
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DOI：
10.5897/ajb09.1225
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发表时间：
2009-11-02
影响因子：
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通讯作者：
Ren Jiangping
中科院分区：
文献类型：
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作者：
Kang Guozhang;Zhu Zhonghou;Ren Jiangping
COR 15 b和KIN 1（COR 6.5）基因分别编码15 KDa和6.5 KDa的多肽。它们参与植物的脱水耐性机制，在低温胁迫下发挥重要作用。本研究首次从西瓜（Citrullus lanatus）和南瓜（Cucurbita moschata）叶片中克隆了COR 15 b和KIN 1基因的cDNA序列。测序结果表明，西瓜和南瓜COR 15 b的开放阅读片段（ORF）分别为348和426 bp，分别编码116和141个氨基酸。CmCOR 15 B b与拟南芥COR 15 B b（AtCOR 15 B b）的氨基酸同源性为98.58%，而ClCOR 15 B b与AtCOR 15 B b的氨基酸同源性仅为80.85%，这是因为ClCOR 15 B b的220（C/T）和418（T/A）位发生了两处突变，T/A突变产生了一个转录物末端密码子（TAA），缺失了26个氨基酸。西瓜KIN 1（ClKIN 1）和南瓜KIN 1（CmKIN 1）的开放阅读框与拟南芥KIN 1（AtKIN 1）相似，均为198 bp，编码两个65个氨基酸的短多肽。ClKIN 1和CmKIN 1的氨基酸序列与AtKIN 1的同源性分别为98.48%和90.51%，但也存在一些突变位点。实时荧光定量PCR结果表明，在低温胁迫下，CmCOR 15 b、ClKIN 1和CmKIN 1的转录量显著增加，表明它们可能参与了抗寒性的调节。而ClCOR 15 b在低温胁迫下保持稳定，说明其在低温胁迫下的作用可能因序列缺失而发生改变。
COR15b and KIN1 (COR 6.5) genes encode polypeptides of 15 KDa and 6.5 KDa, respectively. They are involved in the dehydration tolerance mechanisms and play important role under cold stress. cDNA sequences of COR15b and KIN1 genes were firstly isolated from leaves of watermelon (Citrullus lanatus) and pumpkin (Cucurbita moschata). Sequencing results indicated that the open reading fragments (ORF) of COR15b in watermelon (ClCOR15b) and COR15b in pumpkin (CmCOR15b) were 348 and 426 bp, which encoded 116 and 141 amino acids, respectively. The putative amino acids of CmCOR15 b shared 98.58% identities to COR15b in Arabidopsis (AtCOR15b), but ClCOR15b had only 80.85% identities to AtCOR15b because there appeared two mutations at the positions of 220 (C/T) and 418 (T/A) in ClCOR15b and T/A mutation produced a transcript end codon (TAA), which led to a lack of 26 amino acids. Similar with KIN1 in Arabidopsis (AtKIN1), ORFs of both KIN1 in watermelon (ClKIN1) and KIN1 in pumpkin (CmKIN1) were 198 bp, encoding two short polypeptides of 65 amino acids. The putative amino acids of ClKIN1 and CmKIN1 shared 98.48 and 90.51% identities to AtKIN1 respectively, although they also contained some mutation sites. Real-time quantitative PCR results indicated that, during cold stress condition, transcripts of CmCOR15b, ClKIN1 and CmKIN1 significantly increased, suggesting that they could take part in the cold tolerance. However, ClCOR15b kept stable during cold stress, implying that its role during cold stress could be changed because of the lacked sequence.