A calcium responsive element that regulates expression of two calcium binding proteins in Purkinje cells

Abstract

Calbindin D28 encodes a calcium binding protein that is expressed in the cerebellum exclusively in Purkinje cells. We have used biolistic transfection of organotypic slices of P12 cerebellum to identify a 40-bp element from the calbindin promoter that is necessary and sufficient for Purkinje cell specific expression in this transient in situ assay. This element (PCE1) is also present in the calmodulin II promoter, which regulates expression of a second Purkinje cell Ca 2؉ binding protein. Expression of high levels of exogenous calbindin or calretinin decreased transcription mediated by PCE1 in Purkinje cells 2.5-to 3-fold, whereas the presence of 1 M ionomycin in the extracellular medium increased expression. These results demonstrate that PCE1 is a component of a cell-specific and Ca 2؉ -sensitive transcriptional regulatory mechanism that may play a key role in setting the Ca 2؉ buffering capacity of Purkinje cells.

Zeolite A effect on calcium homeostasis in growing goats1

“…The Ca concentration in the tubular fluid might be involved in regulating RNA expression of CaBP-28k and NCX. This hypothesis is supported by the existence of so-called calcium responsive elements in the promoter region of the CaBP-28k gene in mice (Arnold and Heintz, 1997). However, in the present study, the increase of RNA expression of CaBP-28k…”

Hematopoietic stem cell gene therapy leads to marked visceral organ improvements and a delayed onset of neurological abnormalities in the acid sphingomyelinase deficient mouse model of Niemann–Pick disease

“…Calbindin D28k is a member of the large EF-hand family that is believed to function, in part, as a cytosolic calcium buffer, and encodes a calcium binding protein that is expressed in the cerebellum exclusively in PC. [27][28][29] Our results demonstrated that at 5 months after transplantation, there was an increased number of PC in treated mice as compared with affected, irradiation control mice. These findings were most likely due to the presence of retrovirally transduced, bone marrow-derived microglial cells in the CNS that were capable of secreting ASM in sufficient amounts to delay the disease-specific cell death in PC neurons.…”

Effects of Decreased Calmodulin Protein on the Survival Mechanisms of Alveolar Macrophages during Pneumocystis Pneumonia

“…The CaM1 and CAM3 genes have more than one polyadenylation site, and a total of five calmodulin transcripts may be produced (45). Evidence shows that these transcripts are differentially regulated and transcribed because their promoter sequences possess different combinations of transcription factor binding sites (3,22,57). Only the CaM2 and CaM3 gene mRNA levels in Amø showed changes (Tables 1 and 2) during Pcp, suggesting that there is differential control of calmodulin gene transcription in Amø.…”

“…Phosphatidylinositol (3,4,5)-triphosphate, the product of PI-3K enzymatic activity, mediates Akt-1 (also called protein kinase B) (1,18,29) activation. Akt-1 controls many prosurvival functions (9,10,11,13,23), making PI-3K activation a linchpin of survival signaling.…”