197 Gene targeting of calbindin-d28k reveals a physiological role of an endogenous calcium-binding protein in neuronal calcium signalling

Recurrent implantation failure (RIF) and recurrent pregnancy loss (RPL) are distressing conditions without effective treatments. The luminal epithelium (LE) is integral in determining receptivity of the endometrium, whereas functionalis glands and stroma aid in nurturing early embryo development. Calcium signalling pathways are known to be of vital importance to embryo implantation and pregnancy establishment, and anterior gradient protein 3 (AGR3) and S100 calcium-binding protein P (S100P) are involved with these pathways. We initially examined 20 full-thickness endometrial biopsies from premenopausal women across the menstrual cycle to characterize levels of AGR3 protein in each endometrial sub-region at the cellular level. A further 53 endometrial pipelle biopsies collected in the window of implantation were subsequently assessed to determine differential endometrial AGR3 and S100P levels relevant to RIF (n = 13) and RPL (n = 10) in comparison with parous women (n = 30) using immunohistochemistry. Significantly higher AGR3 and S100P immunostaining was observed in ciliated cells of the LE of women with recurrent reproductive failure compared with parous women, suggesting aberrant subcellular location-associated pathophysiology for these conditions. The nuclear localisation of S100P may allow transcriptional regulatory function, which is necessary for implantation of a viable pregnancy. Further work is thus warranted to assess their utility as diagnostic/therapeutic targets.

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1,25-Dihydroxyvitamin D3-mediated intestinal calcium transport. Biochemical identification of lysosomes containing calcium and calcium-binding protein (calbindin-D28K).

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)66684-0 ◽

1986 ◽

Vol 261 (34) ◽

pp. 16106-16114

Author(s):

I Nemere ◽

V Leathers ◽

A W Norman

Keyword(s):

Calcium Binding ◽

Calcium Transport ◽

Binding Protein ◽

Calcium Binding Protein ◽

Dihydroxyvitamin D3 ◽

1,25 Dihydroxyvitamin D3 ◽

Intestinal Calcium Transport ◽

Biochemical Identification ◽

Calbindin D28k

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Calretinin expression in the mammalian neocortex: a review

Physiological Research ◽

10.33549/physiolres.931930 ◽

2010 ◽

pp. 665-677

Author(s):

F Barinka ◽

R Druga

Keyword(s):

Calcium Binding ◽

Binding Protein ◽

Calcium Binding Protein ◽

Actual Knowledge ◽

Neuronal Homeostasis ◽

Physiological Properties ◽

Cortical Interneurons

In the mammalian neocortex, the calcium-binding protein calretinin is expressed in a subset of cortical interneurons. In the recent years, research on interneurons is one of the most rapidly growing fields in neuroscience. This review summarizes the actual knowledge of the functions of calretinin in neuronal homeostasis and particularly of the distribution, connectivity and physiological properties of calretinin expressing interneurons in the neocortex of rodents and primates, including humans. The possible neuroprotective role of calretinin and the presumed “resistance” of calretinin-expressing interneurons to various pathological processes are also discussed.

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Calcium-binding protein of the chick chorioallantoic membrane. I. Immunohistochemical localization

The Journal of Cell Biology ◽

10.1083/jcb.77.3.743 ◽

1978 ◽

Vol 77 (3) ◽

pp. 743-751 ◽

Cited By ~ 23

Author(s):

RS Tuan ◽

WA Scott ◽

ZA Cohn

Keyword(s):

Calcium Binding ◽

Calcium Transport ◽

External Surface ◽

Binding Protein ◽

Chorioallantoic Membrane ◽

Immunohistochemical Localization ◽

Calcium Binding Protein ◽

Transport Function ◽

Chick Chorioallantoic Membrane

The preparation of a specific antiserum (anti-CaBP) against the calcium-binding protein (CaBP) of the chorioallantoic membrane (CAM) is described. The anti-CaBP appeared to be specific for the CaBP by immunodiffusion and immunoelectrophoresis. Application of the anti-CaBP in immunofluorescence histochemistry revealed that the CaBP is present in the CAM only at developmental ages corresponding with the expression of the calcium transport function of the membrane. Furthermore, the CaBP is localized to the ectoderm of the CAM, appears to be exposed to the entire external surface of the ectoderm, and can be shown to be associated with cells enzymatically dissociated from the CAM. These results are consistent with a functional role of the CaBP in the CAM calcium transport process.

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