籼稻体细胞胚胎发生特异性蛋白质研究

Studies on Specific Proteins of Somatic Embryogenesis in Oryza sativa L. subsp. indica

以籼稻Oryza sativa L. subsp. indica品种“广陆矮4号”幼穗和种子为外植体,在含有2,4-D 2.0mg/L的MS培养基上,分别形成胚性和非胚性愈伤组织,建立体细胞胚胎发生实验系统。应用Native/SDS双向凝胶电泳分析,结果表明,非胚性愈伤组织分化培养前后均存在一种分子量为45kD的非胚性蛋白质N1,另一种非胚性蛋白质N2(54kD)仅在分化培养前的非胚性愈伤组织中含量丰富。胚性愈伤组织则在分化培养后,产生特异性胚胎蛋白质E1(51kD)和E2(68kD)。分化培养基中的蛋白质合成抑制剂亚胺环己酮(CH)抑制E1和E2的产生,转录抑制剂放线菌素D(Act.D)仅抑制E2的出现。

An experimental system of somatic embryogenesis in Oryza sativa L. subsp. indica was established, which involved embryogenic calli induced from rudimentary panicles and nonembryo-genic ones from mature seeds of Guangluai No. 4 (cv. ) ,respectively, on a MS basal medium with 2. 0 mg/L 2,4-D. Profiles of soluable proteins from the calli by native/SDS 2D PAGE ( two dimension polyacrylamide gel electrophoresis ) indicated that a polypeptide of 45 kD(MW) specific to the non-embryonic calli, so called the non-embryonic protein (N1), was consistently present in the non-embryonic ones before and after the calli transfered to a redifferentiation medium, and another non-embryonic protein (N2) of 54 kD rich in before and poor in after the non-embryonic callus transfered to the medium; or that both embryo-specific proteins of 51 kD (E1) and 68 kD (E2) were only present in the embryogenic callus on the redifferentiation medium, but absent from on an induction or a subculture medium with 2,4-D. Cycloheximide (CH), an inhibitor from protein synthesis, suppressed both presences of the El and the E2, while actinomycin D (Act. D), an inhibitor from gene transcription, only suppressed the presence of the E2. It is thence suggested that the El result from regulation on post-transcription of the El gene and the E2 from regulation on transcription of the E2 gene during the somatic embryogenesis.