Howard-Ashby Meredith, Materna Stefan C, Brown C Titus, Chen Lili, Cameron R Andrew, Davidson Eric H
Division of Biology, California Institute of Technology, Pasadena, CA 91125, USA.
Dev Biol. 2006 Dec 1;300(1):74-89. doi: 10.1016/j.ydbio.2006.08.039. Epub 2006 Aug 22.
A set of 96 homeobox transcription factors was identified in the Strongylocentrotus purpuratus genome using permissive blast searches with a large collection of authentic homeodomain sequences from mouse, human and fly. A phylogenetic tree was constructed to compare the sea urchin homeobox gene family to those of vertebrates, with the result that with the only a few exceptions, orthologs of all vertebrate homeodomain genes were uncovered by our search. QPCR time course measurements revealed that 65% of these genes are expressed within the first 48 h of development (late gastrula). For genes displaying sufficiently high levels of transcript during the first 24 h of development (late blastula), whole mount in situ hybridization was carried out up to 48 h to determine spatial patterns of expression. The results demonstrate that homeodomain transcription factors participate in multiple and diverse developmental functions, in that they are used at a range of time points and in every territory of the developing embryo.
利用来自小鼠、人类和果蝇的大量真实同源异型结构域序列进行宽松的blast搜索，在紫球海胆基因组中鉴定出一组96个同源框转录因子。构建了系统发育树，将海胆同源框基因家族与脊椎动物的基因家族进行比较，结果是，除了少数例外，我们的搜索发现了所有脊椎动物同源异型结构域基因的直系同源物。定量聚合酶链反应（QPCR）时间进程测量显示，这些基因中有65%在发育的前48小时（晚期原肠胚）内表达。对于在发育的前24小时（晚期囊胚）显示出足够高转录水平的基因，进行了长达48小时的全胚胎原位杂交，以确定表达的空间模式。结果表明，同源异型结构域转录因子参与多种不同的发育功能，因为它们在发育胚胎的一系列时间点和每个区域都有使用。
