Ferris P J, Goodenough U W
Biology Department, Washington University, St. Louis, Missouri 63130.
Cell. 1994 Mar 25;76(6):1135-45. doi: 10.1016/0092-8674(94)90389-1.
The mating-type locus of Chlamydomonas reinhardtii exists as two apparent alleles (mt+ and mt-) that control mating in haploid gametes and sporulation and meiosis in diploid mt+/mt- zygotes. Twelve genes, seven unrelated to life cycle transitions, are tightly linked to mt, suggesting that the locus exerts recombinational suppression. A 1.1 Mb chromosome walk from a gene linked to mt demonstrates that the mt+ and mt- loci carry four intrachromosomal translocations, two inversions, and large deletions and duplications within a 190 kb sector, presumably accounting for the recombinational suppression that extends through 640 kb of flanking homologous DNA. The rearranged domain also carries blocks of mt(+)- and mt(-)-specific sequences, at least one of which includes a mt(+)-specific gene. The locus has the properties of an incipient sex chromosome.
莱茵衣藻的交配型位点以两个明显的等位基因（mt +和mt -）形式存在，它们控制单倍体配子中的交配以及二倍体mt +/mt -合子中的孢子形成和减数分裂。十二个基因，其中七个与生命周期转变无关，与mt紧密连锁，这表明该位点会产生重组抑制。从一个与mt连锁的基因开始进行的1.1 Mb染色体步移表明，mt +和mt -位点携带四个染色体内易位、两个倒位以及一个190 kb区域内的大片段缺失和重复，这可能是导致延伸至侧翼640 kb同源DNA的重组抑制的原因。重排区域还携带mt（+）和mt（-）特异性序列块，其中至少一个包含mt（+）特异性基因。该位点具有初始性染色体的特性。
