摘要
觅食反应(foraging response)是植物应对矿质养分不足而进化形成的独特机制。本研究发现番茄(Lycopersicon esculentum)幼苗在极度缺氮处理下,整株含氮量明显下降,地上部分生长明显受到抑制,但初生根长度和根总长度显著增加,表现出明显的觅食反应;补充氮后,幼苗生长恢复正常。进一步克隆了番茄SlNPF68基因,发现其开放阅读框长度为1 719 bp,编码572个氨基酸;SlNPF68蛋白分子质量为63.98kDa,理论等电点为9.21,属于碱性不稳定疏水蛋白。序列分析表明SlNPF68属于多肽转运因子(PTR2)家族,与拟南芥(Arabidopsis thaliana) AtNPF4.5、At NPF6.3相似性较高。表达分析表明Sl NPF68基因在番茄根、茎、叶、花、果实等器官中均表达,且受缺氮诱导上调,在3 d后达到最高,随后下降;补充硝酸盐后,其表达量再次上调。在番茄中超量表达SlNPF68基因可显著增加番茄幼苗初生根长度、根总长度以及平均侧根数。综合以上结果,说明SlNPF68可通过响应缺氮参与根系觅食反应。
Foraging response is a unique mechanism evolved in responding to mineral nutrient deficiency in plants. Herein, an obviously foraging response was identified in tomato(Lycopersicon esculentum) seedlings with increased length of primary root and decreased nitrogen content under nitrogen deficiency condition. Besides, the growth of seedlings was significantly inhibited, and was recovered after nitrogen replenishment. Furtherly, a 1 719 bp tomato SlNPF68 gene encoding 572 amino acids was cloned. The molecular mass of SlNPF68 protein is 63.98 kDa, and the theoretical isoelectric point is 9.21, suggesting that the protein is alkaline unstable hydrophobic protein. Amino acid sequence analysis showed that SlNPF68 belongs to PEPTIDE TRANSPORTER2(PTR2) family, which is similar to Arabidopsis thaliana AtNPF4.5 and AtNPF6.3 according to the phylogenetic tree. Reverse transcription PCR analysis indicated that Sl NPF68 gene expressed in tomato root, stem, leaf, flower and fruit. In addition, the expression level of Sl NPF68 was up-regulated after nitrogen starvation cultivation and nitrogen replenishment. Overexpression of Sl NPF68 promoted primary root elongation and lateral root formation. Above results suggest that Sl NPF68is involved in the tomato foraging response by responding to severe nitrogen deficiency.
作者
刘向蕾
尹亚红
高玉迪
李可
刘健
朱友银
LIU Xianglei;YIN Yahong;GAO Yudie;LI Ke;LIU Jian;ZHU Youyin(School of Agriculture,Jinhua Polytechnic,Jinhua,Zhejiang 321007,China;Laboratory of Crop Harvesting Equipment Technology of Zhejang Province,Jinhua,Zhejiang 321007,China;Zhejiang Provincial Key Laboratory of Biotechnology on Specialty Economic Plants,Zhejang Normal University,Jinhua,Zhejiang 321004,China)
出处
《植物生理学报》
CAS
CSCD
北大核心
2022年第7期1212-1220,共9页
Plant Physiology Journal
关键词
番茄
SlNPF68基因
缺氮处理
觅食反应
根系发育
tomato
SlNPF68 gene
nitrogen deficiency treatment
foraging response
root development
