Capdevila M P, Botas J, García-Bellido A
Facultad de Ciencias, U.A.M., Centro de Biologia Molecular, C.S.I.C., Canto Blanco, 28049, Madrid, Spain.
Rouxs Arch Dev Biol. 1986 Sep;195(7):417-432. doi: 10.1007/BF00375746.
We have studied the embryonic and adult phenotypes of genetic combinations between Polycomb (Pc), Regulator of bithorax (Rg-bx) and the genes of the Bithorax complex (BX-C) and the Antennapedia complex (ANT-C). The products of Pc and Rg-bx genes act antagonistically, their mutant combinations leading to the ectopic expression of genes of the BX-C and ANT-C. The genetic analysis of the Pc locus suggests it is a complex gene. Pc products behave as members of a "regulatory set" that negatively control the expression of BX-C and ANT-C genes. Genetic combinations between different doses of Pc, Rg-bx and the genes of the BX-C and ANT-C have phenotypes which may be interpreted as resulting from ectopic derepression of posterior selector genes repressing selector genes of anterior segments. The transformation phenotypes of certain genetic combinations differ in embryos and adults. A model of regulation of the BX-C and the ANT-C genes during the imaginal cell proliferation is presented, in which the specification state is maintained by self-activation of a given selector gene and down modulation of other selector genes in the same cell.
我们研究了多梳基因（Pc）、双胸节调控基因（Rg-bx）与双胸节复合体（BX-C）及触角足复合体（ANT-C）基因之间遗传组合的胚胎期和成体期表型。Pc基因和Rg-bx基因的产物起拮抗作用，它们的突变组合导致BX-C和ANT-C基因的异位表达。对Pc位点的遗传分析表明它是一个复合基因。Pc产物表现为一个“调控组”的成员，该调控组对BX-C和ANT-C基因的表达起负调控作用。不同剂量的Pc、Rg-bx与BX-C和ANT-C基因之间的遗传组合所产生的表型，可能被解释为后选基因的异位去抑制导致前体节选基因被抑制的结果。某些遗传组合的转化表型在胚胎期和成虫期有所不同。本文提出了一个在成虫细胞增殖过程中对BX-C和ANT-C基因进行调控的模型，其中特定选基因的自我激活以及同一细胞中其他选基因的下调维持了细胞的特化状态。
