title: An IQGAP-related gene is activated during tentacle formation in the simple metazoan Hydra.
abstract: Differentiation of body column epithelial cells into tentacle epithelial cells in Hydra is accompanied by changes in both cell shape and cell-cell contact. The molecular mechanism by which epithelial cells acquire tentacle cell characteristics is unknown. Here we report that expression of a Hydra homologue of the mammalian IQGAP1 protein is strongly upregulated during tentacle formation. Like mammalian IQGAP, Hydra IQGAP1 contains an N-terminal calponin-homology domain, IQ repeats and a conserved C terminus. In adult polyps a high level of Hydra IQGAP1 mRNA is detected at the basis of tentacles. Consistent with a role in tentacle formation, IQGAP1 expression is activated during head regeneration and budding at a time when tentacles are emerging. The observations support the previous hypothesis that IQGAP proteins are involved in cytoskeletal as well as cell-cell contact rearrangements.
authors.affiliation: CINVESTAV-IPN, Dept. Genetica, 07000 Mexico.
authors.forename: C R
authors.initials: CR
authors.lastname: Venturelli
authors.forename: S
authors.initials: S
authors.lastname: Kuznetsov
authors.forename: L M
authors.initials: LM
authors.lastname: Salgado
authors.forename: T C
authors.initials: TC
authors.lastname: Bosch
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006829:Hydra / Q000235:genetics / Q000254:growth & development* / Q000502:physiology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012038:Regeneration; D017386:Sequence Homology, Amino Acid; D020703:ras GTPase-Activating Proteins
chemical_list: D002352:Carrier Proteins; D018076:DNA, Complementary; C101203:IQ motif containing GTPase activating protein 1; D020703:ras GTPase-Activating Proteins