苹果CTK响应因子MdRR1的克隆和功能初步分析  

Cloning and Preliminary Functional Analysis of Apple Cytokinin Response Regulator MdRR1

作　　者：陈皓 谢玲玲 孙怡婷 贾鹏 马娟娟 张东 Chen Hao;Xie Lingling;Sun Yiting;Jia Peng;Ma Juanjuan;Zhang Dong(Yangling Subsidiary Center Project of the National Apple Improvement Center,College of Horticulture,Northwest A&F University,Yangling,712100)

机构地区：[1]西北农林科技大学园艺学院,国家苹果改良中心杨凌分中心,杨凌712100

出　　处：《分子植物育种》2021年第17期5612-5622,共11页Molecular Plant Breeding

基　　金：国家自然科学基金(31901969);陕西省科技重大专项(2020zdzx03-01-04);国家苹果产业技术体系“苗木繁育与栽培方式”岗位(CARS-27);唐仲英基金会项目子课题(C200022002);“仲英青年学者”项目(A1190021001)共同资助。

摘　　要：为了探究B型细胞分裂素响应因子RR在苹果腋芽萌发中的功能,以难分枝的一年生‘长富2号’/T337/八棱海棠苹果苗为试验材料,从其腋芽中克隆得到细胞分裂素响应因子家族的1个关键基因MdRR1,其开放阅读框长度为2025 bp,编码674个氨基酸。实时荧光定量PCR分析表明,MdRR1在根中表达量最高,而在腋芽等其他部位较少;6-BA和去顶处理后,MdRR1在腋芽中的表达量显著下调,去顶加Lovastatin(细胞分裂素合成抑制剂)处理与仅去顶处理相比,MdRR1的表达量在处理6 h显著上调。亚细胞定位发现苹果MdRR1基因定位于细胞核。拟南芥中异源过表达苹果MdRR1后其分枝数量较野生型没有显著差异,但对外源独脚金内酯的敏感性降低。这些结果表明,MdRR1可能参与调控苹果腋芽萌发。本研究为苹果优质苗木繁育和省力化栽培中的分枝发育调控提供了理论基础。In order to explore the function of B-type cytokinin response regulator response regulator(RR)in apple axillary bud outgrowth,the one-year-old'Nagafu No.2'/T337/M.robusta Rehd.apple seedlings,which branch difficultly in nature,were used as the main material.MdRR1 a key gene of the cytokinin response regulator family,was cloned from the axillary buds.The open reading frame of MdRR1 is 2025 bp,which encodes 674 amino acids.RT-PCR analysis showed that the expression of MdRR1 was the highest in roots,but less in axillary buds and other tissues.The expression of MdRR1 was significantly down-regulated after 6-BA or decapitation treatments.The application of Lovastatin after decapitation made MdRR1 significantly up-regulated after 6 h compared with only decapitation.Subcellular location showed that MdRR1 was located in the nucleus.The overexpression of MdRR1 transgenic Arabidopsis lines had no significant difference in the number of branches compared with WT,but the sensitivity to exogenous SLs was reduced.These results indicated that MdRR1 might be involved in regulating axillary bud outgrowth in apple.This study provides a theoretical basis for the regulation of branch development in high-quality apple seedling breeding and labor-saving cultivation.

关 键 词：苹果(Malus domestica) MdRR1 基因克隆 表达分析 腋芽萌发 

分 类 号：S661.1[农业科学—果树学]