Lange R G, Müller W A
Zoologisches Institut der Universität, Heidelberg, Federal Republic of Germany.
Dev Biol. 1991 Sep;147(1):121-32. doi: 10.1016/s0012-1606(05)80012-0.
By analogy to processes in angiogenesis (blood vessel formation), the development of the stolonal network in colonial hydrozoa involves stimulation of branching and mutual chemotropic attraction of the growing branches by means of soluble morphogenetic factors. We have identified a glycoconjugate of about 20 kDa, termed SIF (Stolon-Inducing Factor), which induces the formation of stolon branches when applied locally. Micropipettes ejecting SIF mimic the inducing action of stolon tips, the putative sources of SIF. When whole animals are exposed to SIF, stolons sprout not only from the base of the polyps but also from abnormal sites along the entire body, even from the head. In addition, the polyp (hydranth) secretes a chitinous periderm which, in the species under investigation, normally envelops stolons but not hydranths. At high SIF doses the whole hydranth is transformed into stolon tissue. The factor has been isolated from conditioned medium and from butanol extracts of Hydractinia echinata and Podocoryne carnea.
通过与血管生成（血管形成）过程进行类比，群体水螅纲动物中匍匐茎网络的发育涉及通过可溶性形态发生因子刺激分支以及生长分支之间的相互趋化吸引。我们已经鉴定出一种约20 kDa的糖缀合物，称为SIF（匍匐茎诱导因子），当局部应用时，它会诱导匍匐茎分支的形成。微量移液器喷射SIF模拟了匍匐茎尖端（推测的SIF来源）的诱导作用。当整个动物暴露于SIF时，匍匐茎不仅从息肉基部萌发，而且从沿着整个身体的异常部位甚至从头部萌发。此外，息肉（水螅体）分泌一种几丁质外皮，在所研究的物种中，这种外皮通常包裹匍匐茎而不包裹水螅体。在高剂量SIF作用下，整个水螅体转变为匍匐茎组织。该因子已从海仙人掌和角海葵的条件培养基和丁醇提取物中分离出来。
