Research on the action mechanisms of plant hormones

用ABA-AEH Sepharose 4 B亲和层析从绿豆黄化幼苗中分离到一种可溶性脱落酸结合蛋白。其对阿坝的解离常数为10 μ <-7>M。从黄化绿豆幼苗中分离纯化了赤霉素结合蛋白，并以胡萝卜为材料克隆了受生长素和脱落酸调控的胚性细胞蛋白AX 110和ECP 31。从黄瓜幼果切片中分离纯化了生长素诱导的1-氨基环丙烷-1-羧酸（ACC）合成酶，并测定了部分氨基酸序列。根据测定的氨基酸序列合成寡核苷酸，克隆了生长素诱导的南瓜ACC合成酶的cDNA序列，并测定了其序列。将水稻谷氨酰胺合成酶基因RGS-28的5 '侧翼区的一个2-kb片段与GUS报告基因融合，通过农杆菌介导法导入烟草（Nicotianatabacum），获得了一个ACC合成酶基因。 ...更多信息 介导转化启动子响应于外部施加的铵离子。外源GA对水稻种子的影响不明显，单次暴露于DNA去甲基化剂5-氮杂胞苷（aza C）或5-氮脱氧胞苷（aza dC）均能诱导水稻植株矮化。从矮秆植物中克隆了两个基因组，并以玉米赤霉素敏感突变体（d_5）为材料，研究了赤霉素对矮秆生长习性和皮层微管（MT）取向的影响。GA 3处理24 h后，突变体中胚轴的生长受到刺激，表皮细胞和皮层细胞中的MTs横向排列，2-脱氧糖通过降低UDP-糖的水平抑制细胞壁多糖的合成，从而抑制IAA诱导的黄瓜切段细胞伸长。岩藻糖结合凝集素抑制生长素诱导的小豆上胚轴切段伸长。这些凝集素也抑制生长素诱导的细胞壁松散的节。这些结果支持了这样的观点，即木葡聚糖的分解参与了双子叶植物生长素诱导伸长的细胞壁松弛。少

A soluble abscisic acid-binding protein was isolated from etiolated mung bean seedlings by affinity chromatography on ABA-linked AEH Sepharose 4B. Its dissociation constant for ABA was 10^<-7> M. A soluble gibberelic acid-binding protein was also purified from etiolated mung bean seedlings.Embryogenic cell proteins (AX 110 and ECP 31) which synthesis were regulated by auxin and abscisic acid, respectively, were cloned using carrot tissues. 1-Aminocyclopropane-1-carboxylate (ACC) synthase induced by auxin was purified from slices of immature cucumber fruits, and partial amino acid sequences were determined. By using oligonucleotides synthesized based on the determined amino acid sequence, a cDNA for auxin-induced ACC synthase from winter squash was cloned and its sequence was determined.A 2-kb fragment from the 5'-flanking region of the RGS-28 gene (glutamine synthetase from rice) was fused to beta-glucuronidase (GUS) reporter gene and introduced into Nicotiana tabacum by Agrobacterium- … More mediated transformation. The promoter responded to externally applied ammonium ions. However, the effect of externally applied GA was not observed clearly.A single exposure of germinated rice seeds to either the DNA demethylating agents 5-azacytidine (aza C) or 5-azadeoxycytidine (aza dC) induced dwarf plants. Two genomes which were altered by these agents were cloned from dwarf plants.The relationship between the dwarf habit of growth and cortical microtubule (MT) orientation as affected by gibberellin was examined using a gibberellin responsive mutant of Zea mays (d_5). By GA3 treatment for 24h, the growth of d_5 mutant mesocotyls was stimulated, and the orientation of MTs in epidermal cells and cortex cells of Zea mays became transverse.2-Deoxysugars inhibit synthesis of cell-wall polysaccharides by decreasing the levels of UDP-sugars, thereby inhibiting IAA-induced elongation of cells in cucumber segments. Auxin-induced elongation of epicotyl segments of azuki bean was suppressed by fucose-binding lectins. These lectins also inhibited auxin-induced cell wall loosening of segments. These results support the view that the breakdown of xyloglucans is involved in the cell wall loosening responsible for auxin-induced elongation in dicotyledons. Less