|
|
|
|
|
|
|
|
|||||
| Home Help Feedback Subscriptions Archive Search Table of Contents | |||||
Journal of Cell Science, Vol 111, Issue 11 1545-1554, Copyright © 1998 by Company of Biologists
JOURNAL ARTICLES |
AW Koch, TW Holstein, C Mala, E Kurz, J Engel and CN David
Department of Biophysical Chemistry, Biozentrum, University of Basel, Klingelbergstrasse 70, Switzerland.
Here we present the cloning, expression and immunocytochemical localization of a novel 24 kDa protein, designated spinalin, which is present in the spines and operculum of Hydra nematocysts. Spinalin cDNA clones were identified by in situ hybridization to differentiating nematocytes. Sequencing of a full-length clone revealed the presence of an N-terminal signal peptide, suggesting that the mature protein is sorted via the endoplasmic reticulum to the post-Golgi vacuole in which the nematocyst is formed. The N-terminal region of spinalin (154 residues) is very rich in glycines (48 residues) and histidines (33 residues). A central region of 35 residues contains 19 glycines, occurring mainly as pairs. For both regions a polyglycine-like structure is likely and this may be stabilized by hydrogen bond-mediated chain association. Similar sequences found in loricrins, cytokeratins and avian keratins are postulated to participate in formation of supramolecular structures. Spinalin is terminated by a basic region (6 lysines out of 15 residues) and an acidic region (9 glutamates and 9 aspartates out of 32 residues). Western blot analysis with a polyclonal antibody generated against a recombinant 19 kDa fragment of spinalin showed that spinalin is localized in nematocysts. Following dissociation of the nematocyst's capsule wall with DTT, spinalin was found in the insoluble fraction containing spines and the operculum. Immunocytochemical analysis of developing nematocysts revealed that spinalin first appears in the matrix but then is transferred through the capsule wall at the end of morphogenesis to form spines on the external surface of the inverted tubule and the operculum.
This article has been cited by other articles:
|
|
 |
|
  J. S. Hwang, Y. Takaku, J. Chapman, K. Ikeo, C. N. David, and T. Gojobori Cilium Evolution: Identification of a Novel Protein, Nematocilin, in the Mechanosensory Cilium of Hydra Nematocytes Mol. Biol. Evol., September 1, 2008; 25(9): 2009 - 2017. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Krucken, R. J. Hosse, A. N. Mouafo, R. Entzeroth, S. Bierbaum, P. Marinovski, K. Hain, G. Greif, and F. Wunderlich Excystation of Eimeria tenella Sporozoites Impaired by Antibody Recognizing Gametocyte/Oocyst Antigens GAM22 and GAM56 Eukaryot. Cell, February 1, 2008; 7(2): 202 - 211. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. S. Hwang, H. Ohyanagi, S. Hayakawa, N. Osato, C. Nishimiya-Fujisawa, K. Ikeo, C. N. David, T. Fujisawa, and T. Gojobori The evolutionary emergence of cell type-specific genes inferred from the gene expression analysis of Hydra PNAS, September 11, 2007; 104(37): 14735 - 14740. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 U. Engel, S. Oezbek, R. Engel, B. Petri, F. Lottspeich, and T. W. Holstein Nowa, a novel protein with minicollagen Cys-rich domains, is involved in nematocyst formation in Hydra J. Cell Sci., October 15, 2002; 115(20): 3923 - 3934. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Szczepanek, M. Cikala, and C. N. David Poly-{gamma}-glutamate synthesis during formation of nematocyst capsules in Hydra J. Cell Sci., February 15, 2002; 115(4): 745 - 751. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 R Deutzmann, S Fowler, X Zhang, K Boone, S Dexter, R. Boot-Handford, R Rachel, and M. Sarras Molecular, biochemical and functional analysis of a novel and developmentally important fibrillar collagen (Hcol-I) in hydra Development, January 11, 2000; 127(21): 4669 - 4680. [Abstract] [PDF]
|
|
