Weissman I L, Saito Y, Rinkevich B
Department of Pathology, Stanford University, California 94305.
Immunol Rev. 1990 Feb;113:227-41. doi: 10.1111/j.1600-065x.1990.tb00043.x.
Colonial tunicates are complex marine invertebrates (in fact protochordates) that undergo a variety of histocompatibility reactions in their intraspecific competition for feeding surfaces. By means of these reactions colonies fuse with kin, extend domination over a feeding surface, while isolating unrelated conspecifics. The primary determinant of fusion (with kin) or rejection (of non-kin) is a single, highly polymorphic, histocompatibility gene locus (or haplotype), called Fu/HC. Following fusion with nonidentical kin sharing 1 or more Fu/HC allele(s), the fused pair expands both chimeric partners via an asexual budding process, further extending domination over a feeding surface. However, at some later time point an intense set of histoincompatibility reactions occurs between fused kin, resulting in the destruction of all individuals of one of the genotypes, ending the chimeric state. In this review we describe what is known of the genetics and several biological properties encoded by the Fu/HC, and the several independent gene loci that control the colony resorption phenomena that return the colony to the province of a single genotypic individual.
群体被囊动物是复杂的海洋无脊椎动物（实际上是原索动物），它们在种内争夺摄食表面的竞争中会发生多种组织相容性反应。通过这些反应，群体与亲属融合，扩大对摄食表面的控制范围，同时隔离无关的同种个体。融合（与亲属）或排斥（非亲属）的主要决定因素是一个单一的、高度多态的组织相容性基因座（或单倍型），称为Fu/HC。与共享1个或更多Fu/HC等位基因的不同亲属融合后，融合的一对通过无性出芽过程扩展两个嵌合伙伴，进一步扩大对摄食表面的控制。然而，在随后的某个时间点，融合的亲属之间会发生强烈的组织不相容反应，导致其中一种基因型的所有个体被破坏，从而结束嵌合状态。在这篇综述中，我们描述了关于Fu/HC编码的遗传学和几种生物学特性，以及控制群体吸收现象的几个独立基因座，这些现象使群体恢复到单一基因型个体的状态。
