Thomason Peter A, Sawai Satoshi, Stock Jeffry B, Cox Edward C
Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Dev Biol. 2006 Apr 15;292(2):358-70. doi: 10.1016/j.ydbio.2006.01.010. Epub 2006 Feb 13.
A key event in Dictyostelium development is the formation of the Mexican hat. This corresponds to a commitment step in morphogenesis that irreversibly signals progression from the slug stage to the fruiting body. We describe the characterization of the dhkK gene that controls this morphogenetic step. Null mutants of dhkK repeatedly attempt, and fail, to undergo morphogenesis from the slug to the Mexican hat, causing them to exhibit a "slugger" phenotype, which cannot be corrected by co-development with wild-type cells. The dhkK gene encodes a putative receptor histidine kinase whose expression is enriched in prestalk cells in the slug. Uniquely for a histidine kinase, DhkK is located in the nuclear envelope. Entry into culmination requires the DhkK response regulator domain, which appears to directly regulate cyclic AMP signaling.
盘基网柄菌发育过程中的一个关键事件是墨西哥帽的形成。这对应于形态发生中的一个决定步骤，不可逆地标志着从蛞蝓阶段向子实体的进展。我们描述了控制这一形态发生步骤的dhkK基因的特征。dhkK基因的缺失突变体反复尝试从蛞蝓向墨西哥帽进行形态发生，但均失败，导致它们表现出“蛞蝓”表型，与野生型细胞共同发育也无法纠正这一表型。dhkK基因编码一种假定的受体组氨酸激酶，其表达在蛞蝓的前柄细胞中富集。与组氨酸激酶不同的是，DhkK位于核膜上。进入发育后期需要DhkK应答调节结构域，该结构域似乎直接调节环磷酸腺苷信号传导。
