文献类型：期刊文献

中文题名：毛白杨PtoWOX4a基因过表达对次生生长的影响

英文题名：Effect of Overexpression of Populus tomentosa WUSCHEL-related homeobox 4(PtoWOX4a) on the Secondary Growth of Poplar

作者：李建波[1,2] 贾会霞[1] 张进[1] 刘伯斌[1] 胡建军[1] 王丽娟[1] 卢孟柱[1]

第一作者：李建波

通信作者：Lu, Mengzhu

机构：[1]林木遗传育种国家重点实验室中国林业科学研究院林业研究所;[2]中国林业科学研究院华北林业实验中心

年份：2018

卷号：54

期号：2

起止页码：52-59

中文期刊名：林业科学

外文期刊名：Scientia Silvae Sinicae

收录：CSTPCD;;EI(收录号：20182305288883);Scopus(收录号：2-s2.0-85047974040);北大核心:【北大核心2017】；CSCD:【CSCD2017_2018】；

基金：中央级公益性科研院所基本科研业务费专项资金"WOX4与WUSa基因在杨树形成层分化调控中的互作机制"(CAFYBB2014ZX001-1)

语种：中文

中文关键词：毛白杨;PtoWOX4a;基因表达;次生生长;解剖结构

外文关键词：Populus tomentosa;PtoWOX4a;gene expression;secondary growth;anatomical structure

分类号：S718.46

摘要：【目的】WUSCHEL-related homeobox(WOX)转录因子是植物特有的一类转录因子,参与干细胞维持、侧生器官发育和不定根再生等过程,对植物生长发育有至关重要的作用。本文通过对毛白杨Pto WOX4a基因表达模式的分析和过表达植株表型的观察,研究Pto WOX4a在杨树生长发育中的作用,为全面了解不同物种中WOX基因的作用机制奠定基础。【方法】利用qRT-PCR技术分析Pto WOX4a基因在茎顶端分生组织、幼叶、成熟叶、嫩茎、老茎、木质部、韧皮部和根中的相对表达量;利用GUS染色技术对p Pto WOX4a∷GUS转基因植株进行染色,通过GUS信号观察,进一步分析Pto WOX4a在不同组织中的表达模式。对过表达Pto WOX4a植株和对照植株的不定根、茎和叶片进行形态观察和生长指标测定,并通过组织切片对其解剖结构进行观察比较,分析过表达Pto WOX4a对杨树不定根、茎和叶片维管发育的影响。【结果】qRT-PCR结果显示,Pto WOX4a在茎中表达量最高,且主要集中在木质部和韧皮部,在根中表达水平次之,而在叶片等其他组织中的表达量较低;p Pto WOX4a∷GUS转基因植株的GUS染色结果与qRT-PCR结果一致,并发现Pto WOX4a主要在根、叶及茎的维管组织中表达。对过表达Pto WOX4a转基因植株表型观察发现,过表达Pto WOX4a抑制了不定根的伸长,3周苗龄的转基因植株不定根长度约为3~4 cm,仅为对照植株的1/3~1/2,不定根直径变粗,根部木质部区域增加。3月苗龄的过表达Pto WOX4a植株变矮,与对照植株相比,株高减少了14%~20%,节间数减少了16%~22%;对第10节间茎段的解剖结构分析发现,过表达Pto WOX4a植株茎部髓心部分变窄,比对照植株减少了10%~20%,木质部区域变宽,比对照植株增加了24%~35%,而形成层区域宽度无明显变化。此外,过表达Pto WOX4a导致植株叶片生长异常,叶片两侧边缘向上卷曲。【结论】毛白杨Pto WOX4a基因主要在杨树的维管组织中表达,过表达Pto WOX4a可影响杨树不定根、茎和叶片维管的发育。
【Objective】 WUSCHEL-related homeobox（ WOX） is a class of plant specific transcription factors. They play important roles in plant growth and development including stem cells maintaining,lateral organs development,de novo root regeneration of the explant,and other development processes. In this study,the expression patterns and phenotypic traits were analyzed to explore the gene function of Pto WOX4 a and also to provide a basis for comprehensive research on the mechanism of WOX genes in different species.【Method】 The relative expression of Pto WOX4 a in shoot apical meristem,young leaf,mature leaf,tender stem,old stem,phloem,xylem and root in Populus tomentosa were analyzed by qRT-PCR. GUS staining was further analyzed the expression patterns of Pto WOX4 a in different tissues. The genetic effects of Pto WOX4 a on plant development were explored by studying adventitious root（ AR）,stem and leaf morphology and histological anatomy structure in the Pto WOX4 a overexpression poplar.【Result】 qRT-PCR result showed that the highest accumulation of Pto WOX4 a transcripts was observed in stem,followed by root and leaf. The result of GUSstaining was consistent with the qRT-PCR result,revealing that Pto WOX4 a was mainly expressed in the vascular tissue of AR,leaf and stem. In 3-week-old seedlings,overexpression of Pto WOX4 a shortened the AR length to 3-4 cm,which was only 1/3-1/2 compared with the control; overexpression of Pto WOX4 a increased AR diameter and promoted xylem cell differentiation in AR. In 3-month-old plants,the overexpression of Pto WOX4 a transgenic plants showed dwarf phenotype. Compared with the control,they exhibited 14%-20% decrease in stem height,16%-22% decrease in internode number. In the tenth internode,the transgenic plants showed 10%-20% decrease in the width of pith parenchyma cells,24%-35% increase in the width of xylem,but the width of cambium did not change significantly.Furthermore,overexpression of Pto WOX4 a caused the upward leaf curling.【Conclusion】 Pto WOX4 a mainly expresses in the vascular tissue of poplar. Overexpression of Pto WOX4 a affects the development of vascular tissues of poplar root,leaf and stem.