Temporally and spatially restricted expression of a gland cell gene during regeneration and in vitro transdifferentiation in the hydrozoan Podocoryne carnea

Abstract

An antiserum to transdifferentiated striated muscle cells from the medusa of Podocoryne carnea was prepared and used to screen a λ gt11-expression library prepared from gonozoids of P. carnea. We isolated a cDNA clone termed Pod-EPPT with at least 63 tandem repeats of the tetrapeptide-motive glu-pro-pro-thr, named Pod-EPPT. Using Pod-EPPT as a molecular marker for head quality the morphological relationship between the two metagenic life stages of this hydroid, the polyp and the medusa, was studied. In situ hybridization demonstrated that expression of the gene corresponding is restricted to secretory cells in the endoderm of the oral hypostome region of polyps and medusae and, presumably, to progenitor cells of this type. Cells expressing Pod-EPPT could not be observed in the larval stage. During head regeneration in polyps, Pod-EPPT expression is upregulated soon after head removal in previously non-expressing cells and in newly differentiating secretory cells. This activation of a head-specific gene precedes the morphologically obvious events of head regeneration. Pod-EPPT is one of the genes that are activated during manubrium (mouth) regeneration from experimentally combined subumbrellar plate endoderm and striated muscle of the medusa.

Isolation of a marker for head-specific cell differentiation in hydra

“…Alternatively, the positive overall charge and the various putative phosphorylation sites found in the hyp 1 encoded protein, might speak in favour of an intracellular location. In tissue distribution the hyp 1 message is similar to that of another gene, Pod-EPPT, which has been cloned from the marine hydrozoa Podocoryne carnea [1]. The protein encoded by that gene contains 63 tandem repeats of the tetrapeptide-motif glutamic acid-proline-prolinethreonine, which makes its sequence completely different from that of hyp 1-encoded protein.…”

Functional differentiation of the sugar beet root system as indicator of developmental phase change

“…Cell vesicular trafficking plays a pivotal role during plant development regulating the transport of transcripts and metabolites (Bollman et al 2003, Surpin and Raikhel 2004, Ueda and Nakano 2002). Secretory endostyle and Sec 1 precursor proteins are involved in maintaining the trafficking of secretory vesicles (Bracher and Weissenhorn 2002, Fujita and Nanba 1971) while Pod‐EPPT proteins stimulate the proliferation of secretory vesicles in undifferentiated cells but not in functionally differentiated cells (Baader et al 1995).…”

“…Plant. 135, 2009 trafficking of secretory vesicles (Bracher andWeissenhorn 2002, Fujita andNanba 1971) while Pod-EPPT proteins stimulate the proliferation of secretory vesicles in undifferentiated cells but not in functionally differentiated cells (Baader et al 1995).…”

The hydrozoan life cycle: a small secreted protein is involved in specification of the polyp stage

“…In situ hybridization on cryo-sections was performed as described in the manual for nonradioactive in situ hybridization (Boehringer-Mannheim). For in situ hybridization on whole mount and single cell preparations the protocol described by Baader et al (1995) was used.…”