High impact information on S100G

• Site-site communication in the EF-hand Ca2+-binding protein calbindin D9k [1].
• Energy-based de novo protein folding by conformational space annealing and an off-lattice united-residue force field: application to the 10-55 fragment of staphylococcal protein A and to apo calbindin D9K [2].
• Proline isomerism leads to multiple folded conformations of calbindin D9k: direct evidence from two-dimensional 1H NMR spectroscopy [3].
• Here, we report the identification of two VD response elements consisting of inverted palindromes spaced by nine nucleotides (IP9s) in the promoters of the human calbindin D9k gene and the rat osteocalcin gene [4].
• Functional properties of calbindin D9K mutants with exchanged Ca2+ binding sites [5].

Biological context of S100G

• Control of differentiation-induced calbindin-D9k gene expression in Caco-2 cells by cdx-2 and HNF-1alpha [6].
• A sequence positioned 50 nucleotides downstream from the promoter showed extensive homology to the estrogen response element at the same location within the rat calbindin-D9k gene [7].
• The full-length cDNA encoding the human calbindin-D9k (CaBP-9k) has been cloned using reverse transcription/PCR methodology with rat- and bovine-derived primers and intestinal RNA [8].
• We have constructed three different engineered proteins based on calbindin D9K by either exchanging the two calcium binding sites within the protein or making the amino acid sequence of the two calcium binding sites identical [5].
• Measurements included: biochemical parameters of bone remodeling (plasma osteocalcin and urinary pyridinolines); histomorphometry of proximal tibial metaphysis; DXA of femur; biomechanical analysis of femur and fifth lumbar vertebra (L5); plasma 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and calbindin-D9K in duodenal mucosa [9].

Anatomical context of S100G

• Calbindin-D9K gene expression in human myometrium during pregnancy and labor [10].
• The data suggest that calbindin-D9k is required for mineral nucleation in the matrix vesicles of epiphyseal cartilage and bone [11].
• Theoretical and experimental results for calbindin D9k, granulocyte colony stimulating factor, and ubiquitin, three proteins with different distributions of N-H and C alpha-H alpha bond vectors, are used to illustrate the advantages of the simultaneous utilization of 13C alpha and 15N relaxation data [12].
• In the pons, cabp(+) cells and neuropil could be seen in the medial and lateral pontine nuclei (pontine gray) [13].
• The inferior colliculus had a relatively low density of cabp(+) cells [13].

Associations of S100G with chemical compounds

• The 9,000 Mr calcium-binding protein calbindin-D9k (CaBP9k) is markedly induced by 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3] in mammalian intestine [14].
• The human calbindin-D9k gene. Complete structure and implications on steroid hormone regulation [7].
• The mRNA levels of renal 25-hydoxyvitamin D 24-hydroxylase (24OHase) increased, whereas those of renal 25-hydroxyvitamin D 1-alpha hydroxylase (1alpha-hydroxylase), duodenal transient receptor potential cation channel, subfamily V, member 6 (TRPV6), TRPV5, and calbindin-D9k were all decreased [15].
• Measurement and modelling of sequence-specific pKa values of lysine residues in calbindin D9k [16].
• However, some EF-hand proteins, such as calbindin D9k (Clb), bind Ca(2+) without a significant change in conformation [17].

Other interactions of S100G

• In addition, expression of CYP3A4 mRNA in a panel of duodenal samples was significantly correlated with the mRNA level of a known vitamin D receptor gene target, calbindin-D9K [18].
• Moreover, the increase in CaT1 mRNA expression preceded by several hours the vitamin D induction of calbindin D9K, a putative cytosolic calcium transport protein [19].
• This analysis was extended to a comprehensive comparison of the three-dimensional structures of the calcyclin monomer subunit and calbindin D9k, which revealed greater similarity in the packing of their hydrophobic cores than was anticipated previously [20].
• CONCLUSION: In normal humans, 1, 25-dihydroxycholecalciferol has a small but significant relationship to duodenal expression of calbindin-D9k, but not to PMCA1 expression [21].
• ESI-MS showed that wild-type calbindin D9K binds two Ca2+ ions with similar affinities while the binding of two Cd2+ ions is sequential, as is the binding of the two Ca2+ or Cd2+ ions to the N56A mutant of calbindin [22].

Analytical, diagnostic and therapeutic context of S100G

• Molecular cloning of the full-length cDNA encoding the human calbindin-D9k [8].
• A pH titration study of calbindin D9k was performed using heteronuclear 1H-13C two-dimensional NMR spectroscopy [16].
• The data for the apo and (Cd2+)1 states were compared to those for the (Ca2+)2 state [Kördel, J., Skelton, N. J., Akke, M., Palmer, A. G., & Chazin, W. J. (1992) Biochemistry 31, 4856-4866] to ascertain the effects on ion ligation on the backbone dynamics of calbindin D9k [23].
• Dissection of calbindin D9k into two Ca(2+)-binding subdomains by a combination of mutagenesis and chemical cleavage [24].
• Determination of the metal-binding cooperativity of wild-type and mutant calbindin D9K by electrospray ionization mass spectrometry [22].

References