CAJ | 학술논문

MYB 类转录因子是植物中最大的转录因子基因家族之一，广泛参与植物生长发育全过程，对植物次生代谢等具有重要的调控作用。本研究对大豆GmMYB042基因的表达特性和功能进行了系统研究，针对该基因C端的保守氨基酸基序(PDLNLELTIS)和锌指结构进行了一系列的序列删除突变，并将各缺失突变体在烟草中进行了过表达，以验证目的基因及其特殊基序的功能。表达特性分析结果表明， GmMYB042基因在大豆的根瘤、根、茎、叶、花、荚果皮和种子中均有表达，且在茎、种子和花中的表达量相对较高；GmMYB042基因在大豆中的表达受PEG、高盐、低温和UV-B辐射的诱导。过表达分析结果表明， GmMYB042基因的过表达使转基因烟草类黄酮代谢途径部分关键酶基因(如PAL、CHS和FLS)的表达量明显上升，转基因烟草总黄酮的含量明显高于对照；各缺失突变体的转基因烟草类黄酮代谢途径相应酶基因的表达量发生了相应的变化，进一步证明目的基因对类黄酮生物合成的调控作用；各缺失突变体的转基因烟草的叶缘有明显皱褶，说明目的基因可能还参与调控叶的形态建成。
MYB 류전록인자시식물중최대적전록인자기인가족지일，엄범삼여식물생장발육전과정，대식물차생대사등구유중요적조공작용。본연구대대두GmMYB042기인적표체특성화공능진행료계통연구，침대해기인C단적보수안기산기서(PDLNLELTIS)화자지결구진행료일계렬적서렬산제돌변，병장각결실돌변체재연초중진행료과표체，이험증목적기인급기특수기서적공능。표체특성분석결과표명， GmMYB042기인재대두적근류、근、경、협、화、협과피화충자중균유표체，차재경、충자화화중적표체량상대교고；GmMYB042기인재대두중적표체수PEG、고염、저온화UV-B복사적유도。과표체분석결과표명， GmMYB042기인적과표체사전기인연초류황동대사도경부분관건매기인(여PAL、CHS화FLS)적표체량명현상승，전기인연초총황동적함량명현고우대조；각결실돌변체적전기인연초류황동대사도경상응매기인적표체량발생료상응적변화，진일보증명목적기인대류황동생물합성적조공작용；각결실돌변체적전기인연초적협연유명현추습，설명목적기인가능환삼여조공협적형태건성。
MYB transcription factor is one of the largest transcription factor gene families in land plants, and is involved in a myriad of regulatory processes, such as secondary metabolism. In the present study, the expression profiles and function of GmMYB042 gene were systematically studied. In order to investigate the roles of the conserved amino acid motif PDLNLELTIS and a predicted zinc finger region at its C-terminal, a series of sequence deletions of these two regions were made by PCR method. Subsequently, the corresponding over-expression constructs of GmMYB042 gene and its mutants were made and transformed into tobacco NC89 with Agrobacterium LBA4404, respectively. Expression analyses revealed that GmMYB042 gene was expressed in nodule, root, stem, leaf, flower, pod, and seed of soybean, and with a relative higher expression level in stem, flower, and seed;its expression could be induced by PEG, high salt, low temperature, and UV-B radiation stresses. Over-expression analyses showed that the expressions of some enzyme genes in flavonoid biosynthesis pathway (including PAL, CHS, CHI, and FLS) were obviously increased in GmMYB042 transgenic lines, resulting in an increased content of the flavonoid compounds. Accordingly, the transcription levels of the corresponding enzyme genes involved in flavonoid biosynthesis pathway were decreased in the transgenic lines of GmMYB042 mutants, further supporting the conclusion of regulating role of GmMYB042 gene in tobacco fla-vonoid biosynthesis pathway.