Immunolocalization of calcium vector protein and its target protein in amphioxus

Article Article scientifique Article Immunolocalization of calcium vector protein and its target protein in amphioxus eng 1993-07 author Valette Laurence Agnes 46782 author Comte Michelle 26003 author Chaponnier Christine 25579 author Cox Jos Adrian 25544 73-81 10.1007/BF00268880 8226110 0301-5564 http://link.springer.com/10.1007/BF00268880 Three proteins, sarcoplasmic CA2+-binding protein (SCP), Ca2+ vector protein (CaVP) and its target protein (CaVPT), are found abundantly in the higher invertebrate amphioxus. Whereas the function of SCP is likely to be related to Ca2+ and Mg2+ buffering, that of the latter two proteins, apparently linked together, is still not clear. In this study, affinity-purified polyclonal antibodies to these three proteins were used to study the extractability under physiological ionic conditions, the distribution in different tissues and the immunocytochemical localization in striated muscle. Our data show that SCP is essentially cytosolic whereas CaVP and CaVPT are partially associated with non-soluble components in amphioxus tissues. The tissue distribution, studied in transverse sections, shows that SCP is merely confined to striated muscle, whereas CaVP and CaVPT are also abundant in other tissues such as the spinal chord and the gonads. Thus the protein pair CaVP/CaVPT is likely to serve a general role in many tissues; however, no strict correlation was found in the distribution of the latter two proteins, suggesting that they may function independently. The detailed cytochemical localization of the three proteins in longitudinal sections of striated muscle revealed a discrete striation pattern in addition to a diffuse background. For SCP these striations are coincident with the Z line. The immunostaining for CaVP shows intense striations at the level of the Z lines alternating with weak striations at the M lines. For CaVPT the striations at the Z and M line are more or less of equal intensity, leading to a pattern with a 1μm periodicity. The data lead to the conclusion that CaVP and CaVPT can form dynamic complexes with structural components of the sarcomere. Striate Muscle Target Protein Transverse Section Longitudinal Section Ionic Condition Dewey 540 Dewey 616.07 39 Département de biochimie 144 137 Département de pathologie et immunologie 21F false Histochemistry 100 1 942e919a-5e2e-419f-b023-3227eb51bfa2 Article (Published version) Public Article-scientifique-from-crossref.pdf 2975990 application/pdf OA NATIONAL openAccess Faculté des sciences / Section de chimie et biochimie / Département de biochimie Faculté de médecine / Section de médecine fondamentale / Département de pathologie et immunologie

Title	Published in	Year	Views	Downloads

Immunolocalization of calcium vector protein and its target protein in amphioxus	Histochemistry	1993	186	200
Primary structure of three minor isoforms of amphioxus sarcoplasmic calcium-binding proteins	FEBS letters	1992	483	0

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Valette, Laurence Agnes