Page 44 - 《广西植物》2024年第2期
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2 4 6                                  广  西  植  物                                         44 卷
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                       ZHANG Shixin ꎬ WU Shaohua ꎬ YANG Shuguang ꎬ CHAO Jinquan ꎬ
                                           1           1ꎬ2            1ꎬ2                1∗
                              SHI Minjing ꎬ GE Lixin ꎬ JIANG Yi ꎬ TIAN Weimin
              ( 1. Rubber Research Instituteꎬ Chinese Academy of Tropical Agricultural Sciences / National Key Laboratory for Tropical Crop Breeding / Key
             Laboratory of Biology and Genetic Resources of Rubber Treeꎬ Ministry of Agriculture and Rural Affairs / Hainan Key Laboratory for Cultivation &
            Physiology of Tropical Cropsꎬ Haikou 571101ꎬ Chinaꎻ 2. Tibet Agricultural and Animal Husbandry Universityꎬ Nyingchi 860000ꎬ Xizangꎬ China )

                 Abstract: The secondary laticifer is the position for synthesis and storage of natural rubber ( NR)ꎬ which is
                 differentiated from the vascular cambium cells of bark in stem of rubber trees (Hevea brasiliensis). The quantity of
                 secondary laticifer is depended on the frequency of the secondary laticifer differentiation from cambiaꎬ which is the main
                 index of yield breeding of rubber tree. In previous studiesꎬ we found trichostatin A (TSA)ꎬ an inhibitor of histone
                 deacetylase ( HDA)ꎬ can also induce laticifer differentiationꎬ and the histone deacetylase gene ( HbHDA6) is a
                 participator in laticifer differentiation. Because of the molecular mechanism of secondary laticifer differentiation regulated
                 by histone acetylation has not been clarified. Thereforeꎬ we construct a yeast two ̄hybrid cDNA library used the vascular
                 cambium tissues treatment by coronatine (COR)ꎬ and screening the yeast two ̄hybrid library by HbHDA6 gene as the
                 baitꎬ for determining the proteins interacting with HbHDA6. The results were as follows: (1) The homogenized yeast
                 two ̄hybrid cDNA library of vascular cambium was constructed by the technology of Gateway. The capacity of the primary
                                6         ̄1                              7
                 library was 6.34 × 10 CFUmL ꎬ the total number of clones was 1.27 × 10 ꎬ and the capacity of secondary library was
                        6         ̄1                               7
                 7.72 × 10 CFUmL ꎬ the total number of clones was 1.54 × 10 ꎬ and the recombination rates of two libraries were
                 100%. The average length of inserted fragments was 1. 1 kb and 1. 2 kb in primary and secondary libraryꎬ
                 respectively. ( 2) The bait vector of pGBKT7 ̄HbHDA6 for screening the proteins interacting with HbHDA6 was
                 successfully constructed and confirmed no self ̄activation activity. (3) The pGBKT7 ̄HbHDA6 bait vector was used to
                 screen the constructed yeast two ̄hybrid cDNA libraryꎬ and 22 proteins interacting with HbHDA6 were obtained by
                 NCBI_BLAST comparison and removing duplicatesꎬ including CLP1ꎬ ERF3ꎬ ERF4ꎬ HSP82ꎬ LARP6aꎬ APT5ꎬ PP2Aꎬ
                 APT5ꎬ FBA6ꎬ etc. The results provide a theoretical basis for analyzing the molecular regulatory network of the secondary
                 laticifer differentiation of rubber treeꎬ and provide candidate genes for the rubber production potential of genetically
                 modified and a new clue for the genetic improvement and breeding of high ̄performance NR.
                 Key words: Hevea brasiliensisꎬ secondary laticifer differentiationꎬ vascular cambiumꎬ yeast two ̄hybridꎬ HbHDA6




                天然橡胶是关系国民生计的重要工业原料和                            层细胞分化成次生乳管(Hao & Wuꎬ 2000ꎻ 刘惠芳
            战略物资ꎬ世界所需的天然橡胶主要来自巴西橡胶                             等ꎬ2001ꎻ Tian et al.ꎬ 2003)ꎻ我们后续又发现与 JA
            树(Hevea brasiliensis)(田维敏等ꎬ2015)ꎮ 橡胶树树             的活性形式 JA ̄Ile 结构相似的冠菌素( coronatineꎬ
            干树皮中的次生乳管是天然橡胶合成和贮存的主                              COR)(Ichihara et al.ꎬ 1977)ꎬ在诱导橡胶树次生乳
            要场所ꎬ是由维管形成层纺锤状原始细胞分化而来                             管分化的效应方面比茉莉酸甲酯(methyl jasmonateꎬ

            ( Gomezꎬ 1982ꎻ Hao & Wuꎬ 2000ꎻ Chao et al.ꎬ        MeJA)更好(张世鑫等ꎬ2011ꎻZhang & Tianꎬ 2015)ꎬ
            2023)ꎮ 随着形成层分化的次生乳管不断向外推                           并建立了一种稳定的 COR 诱导橡胶树萌条次生乳
            移ꎬ要经过幼嫩—成熟—衰老—死亡ꎬ为维持产胶                             管分化的实验系统(Zhang & Tianꎬ 2015ꎻ Zhang et
            部位的乳管数量ꎬ需要形成层不断分化出新的次生                             al.ꎬ 2015ꎬ 2016ꎻ Wu et al.ꎬ 2016ꎬ 2023ꎻ 张世鑫等ꎬ
            乳管ꎮ 这些次生乳管的数量与天然橡胶产量直接                             2018)ꎮ 最近ꎬ我们发现组蛋白去乙酰化酶(histone
            相关ꎬ次生乳管数量取决于维管形成层分化次生乳                             deacetylaseꎬ HDA ) 的 抑 制 剂———曲 古 抑 菌 素 A
            管的频率(即次生乳管分化能力)ꎬ是橡胶树产量育                            (trichostatin AꎬTSA)也能诱导橡胶树次生乳管分化

            种的主要指标(田维敏等ꎬ2015ꎻ Chao et al.ꎬ 2023)ꎮ              (Zhang et al.ꎬ 2016)ꎬ使用 COR 处理能够显著提高
            前期研究中ꎬ我们团队发现外施茉莉酸( jasmonicꎬ                       形成层区的组蛋白乙酰化程度且 HDA 活性和含量
            JA)及其前体亚麻酸(linolenic acidꎬLA)能诱导形成                 也受影响ꎮ 基于这些工作基础ꎬ以及组蛋白乙酰化
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