Alpha-Tocopherol Transfer Protein (TTPa)

AVED; TTP1; alphaTTP; Ataxia(Friedreich-Like)With Vitamin E Deficiency

SPN	P757
HGNC	12404
MGI	1354168
PubMed	23186252
RGD	3915
UniProt	P49638

TTPa encodes a soluble protein that binds alpha-trocopherol, a form of vitamin E, with high selectivity and affinity. This protein plays an important role in regulating vitamin E levels in the body by transporting vitamin E between membrane vesicles and facilitating the secretion of vitamin E from hepatocytes to circulating lipoproteins. Mutations in this gene cause hereditary vitamin E deficiency (ataxia with vitamin E deficiency, AVED) and retinitis pigmentosa.

Using rat alpha-Ttp to screen a liver cDNA library, followed by PCR, Arita et al. (1995) cloned full-length human alpha-TTP. The deduced 278-amino acid protein has a calculated molecular mass of 31.7 kD and shares 94% identity with rat alpha-Ttp. Northern blot analysis of several human tissues detected a 4.5-kb alpha-TTP transcript in liver only.

Reference

"Human alpha-tocopherol transfer protein: cDNA cloning, expression and chromosomal localization."
Biochem. J. 306:437-443(1995) [PubMed] [Europe PMC] [Abstract]

"Human alpha-tocopherol transfer protein: gene structure and mutations in familial vitamin E deficiency."
Ann. Neurol. 39:295-300(1996) [PubMed] [Europe PMC] [Abstract]

"The status, quality, and expansion of the NIH full-length cDNA project: the Mammalian Gene Collection (MGC)."
Genome Res. 14:2121-2127(2004) [PubMed] [Europe PMC] [Abstract]

"Ataxia with isolated vitamin E deficiency: heterogeneity of mutations and phenotypic variability in a large number of families."
Am. J. Hum. Genet. 62:301-310(1998) [PubMed] [Europe PMC] [Abstract]

"Ataxia with isolated vitamin E deficiency is caused by mutations in the alpha-tocopherol transfer protein."
Nat. Genet. 9:141-145(1995) [PubMed] [Europe PMC] [Abstract]

"An enzyme assisted RP-RPLC approach for in-depth analysis of human liver phosphoproteome."
J. Proteomics 96:253-262(2014) [PubMed] [Europe PMC] [Abstract]

"The molecular basis of vitamin E retention: structure of human alpha-tocopherol transfer protein."
J. Mol. Biol. 331:725-734(2003) [PubMed] [Europe PMC] [Abstract]

"Crystal structure of human alpha-tocopherol transfer protein bound to its ligand: implications for ataxia with vitamin E deficiency."
Proc. Natl. Acad. Sci. U.S.A. 100:14713-14718(2003) [PubMed] [Europe PMC] [Abstract]

"Adult-onset spinocerebellar dysfunction caused by a mutation in the gene for the alpha-tocopherol-transfer protein."
N. Engl. J. Med. 333:1313-1318(1995) [PubMed] [Europe PMC] [Abstract]

"Molecular determinants of heritable vitamin E deficiency."
Biochemistry 43:4143-4149(2004) [PubMed] [Europe PMC] [Abstract]

"Ataxia with isolated vitamin E deficiency: neurological phenotype, clinical follow-up and novel mutations in TTPA gene in Italian families."
Neurol. Sci. 25:130-137(2004) [PubMed] [Europe PMC] [Abstract]