Gene Superfamily

In the treatment of diseases where the metaboUtes are not being deUvered to the system, synthetic metaboUtes or active analogues have been successfully adrninistered. Vitamin metaboUtes have been successfully used for treatment of milk fever ia catde, turkey leg weakness, plaque psoriasis, and osteoporosis and renal osteodystrophy ia humans. Many of these clinical studies are outlined ia References 6, 16, 40, 51, and 141. The vitamin D receptor complex is a member of the gene superfamily of transcriptional activators, and 1,25 dihydroxy vitamin D is thus supportive of selective cell differentiation. In addition to mineral homeostasis mediated ia the iatestiae, kidney, and bone, the metaboUte acts on the immune system, P-ceUs of the pancreas (iasulin secretion), cerebellum, and hypothalamus. 

Members of the immunglobulin gene superfamily (VCAM-1, ICAM-1, ICAM-2)... 

Glusman G., Bahar A., Sharon D., Pilpel Y., et al. (2000). The olfactory receptor gene superfamily data mining, classification, and nomenclature. Mamm Genome 11, 1016-1023. 

Sharon D., Glusman G., Pilpel Y., Hom-Saban S. and Lancet D. (1998). Genome dynamics, evolution, and protein modelling in the olfactory gene superfamily. Ann NY Acad Sci 855, 182-193. 

Mackenzie PI, Owens IS, Burchell B, Bock KW, Bairoch A, Belanger A et al. The UDP glycosyltransferase gene superfamily recommended nomenclature update based on evolutionary divergence. Pharmacogenetics 1997 7[4] 255-269. 

Gonzalez FJ, Nebert DW. Evolution of the P450 gene superfamily animal-plant warfare , molecular drive, and human genetic differences in dmg oxidation. Trends Genet 1990 6 182-186. 

Facilitated diffusion of glucose across the blood-brain barrier and into brain cells is catalyzed by GLUT1,- 2 and -3, products of the SLC2 gene superfamily 90... 

The ABC transporters are products of one of the largest gene superfamilies. Each consists of two cytoplasmic nucleotide-binding domains (NBDs) and two transmembrane domains (TMDs). The NBDs are highly conserved across the ABC family and contain motifs typical of ATP-binding sites, whereas the TMD structures vary, probably because they are adapted to the wide variety of substrates. In eukaryotes the C-terminal of each NBD is linked to a TMD. In some cases the functional unit is (NBD-TMD)2 and, in others, the first TMD is covalently linked to the second NBD. 

FIGURE 7-1 The immunoglobulin (Ig) gene family of molecules. Several varieties of Ig domain-containing molecules are contained within the Ig gene superfamily. Most are type I membrane proteins some have only Ig domains or other moieties that may convey function (see text). V, variable Ig domain C, constant Ig domain MAG, myelin-associated glycoprotein NCAM, neural cell adhesion molecule GPI, glycosylphosphatidyl-inositol EC, extracellular domain FN, fibronectin. 

Glycine receptors belong to the same gene superfamily as does the GABAa receptor 299... 

P450 gene superfamily an effective means of protection against a variety of dietary compounds (Scott and Wen 2001). 

Schoepfer R, Conroy WG, Whiting P, Gore M, Lindstrom J (1990) Brain a-bungarotoxin binding protein cDNAs and MAbs reveal subtypes of this branch of the ligand-gated ion channel gene superfamily. Neuron 5 35 8... 

Some sensory neurons of the VNO express two gene superfamilies, termed Vlr and V2r, that encode over 240 proteins of the seven-transmembrane type (Matsunami and Buck, 1997). These G-protein-linked putative pheromone receptors are distantly related to the main olfactory system s receptors. Receptors of the VNO are linked to different G-proteins, and their extracellular N-terminal domains are longer than those of the receptors in the main olfactory system. (Vi receptors are linked to Gi-proteins and V2 receptors to Go-proteins). The intracellular excitation mechanism in VNO sensory neurons also differs from that in the main olfactory systems instead of linking to adenylyl cyclase, the VNO receptors activate the phosphoinositol second messenger system. This has been demonstrated in several mammalian species. In hamsters, aphrodisin increases inositol 1,4,5-trisphosphate (IP3) levels in VNO membranes. Boar seminal fluid and urine stimulate increases of IP3 in the VNO of the female pig. (However, in the pig, the VNO is not necessarily essential for responses to pheromones [Dorries etal., 1997]). 

Platelets also express adhesion receptors of the selectin gene family (P-selectin) and of the immunoglobulin gene superfamily (PECAM-1 and ICAM-2) (6). Expression of PECAM-1 and ICAM-2 may play a role in platelet interactions with endothelial cells and leukocytes, respectively. 

Ibrahim, R.K. and Muzac, L, The methyltransferase gene superfamily a tree with multiple branches, in Evolution of Metabolic Pathways, Romeo, J.T., Ibrahim, R., Varin, L., and De Luca, V., Eds., Elsevier Science Ltd, Oxford, 2000, 349. 

Maekenzie PI, Boek KW, Burehell B et al. Nomenclature update for the mammalian UDP glycosyl-transferase (UGT) gene superfamily. Pharmacogenet Genomics 2005 15 677-685. Radominska-Pandya A, Czernik PJ, Little JM et al. Struetural and funetional studies of UDP-glueuronosyltransferases. DrugMetab Rev 1999 31 817-899. 

Nebert DW, Gonzales F. The P450 gene superfamily. In Ruckpaul K, Rein H, ed. Frontiers of Biotransformation. Vol. 2. Principles, Mechanisms and Biological Consequences of Induction. London Taylor Francis, 1990. 

Nebert DW. The P450 gene superfamily recommended nomenclature and updates. Nelson DR, Koymans L, Kamataki T, et al. The P450 superfamily update on new sequences, gene mapping, accession numbers, and nomenclature. Pharmacogenetics 1996 6 1-42. Previous updates 1987/1989/ 1991/1993) in DNA Cell Biol. 6, 1-11 8, 1-13 10 1-14 12, 1-51. 

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