Difference between revisions of "Part:BBa K1470000"

Revision as of 16:15, 6 October 2014

Ecotropic murine leukemia virus (MuLV) receptor / Cationic amino acid transporter 1 (CAT-1)

The cationic amino acid transporter 1 (CAT-1) is a part of the CAT family which is the main entry gate for amino acids such as histidine, arginine or ornithin in mammalian cells. They enable the influx of their substrate in a Na<up>+</up> independent way and also under certain circumstances the eflux [1].

Structure and virus recognition

CAT-1 is a 66 kDa membrane protein. It's built up of 622 amino acids contains 14 transmembrane domains which resolutes in seven extracellulare and eight intracellulare domains. There are two sites for N-glycosylation in the third extracellulare loop[2]. Also a comparison between CAT-1 sequences from different species shows that this region doesn't include conserved amino acids.

The glycosyled position is very important for virus' entry. The murine leukeamia virus is only able to enter the cell, when it detects the SLC7A1's sugar-bound moieties. Otherwise MuLV doesn't infect cells [2].

Physiology

CAT-1 was shown to be be responsible for the cationic amino acid influx. Absence of the protein leads to smaller and anemic cells and not viable mice pubs [3].

References

[1]
Transport of cationic amino acids by the mouse ecotropic retrovirus receptor. J. W. Kim, E. I. Closs, L. M. Albritton, J. M. Cunningham Nature. 1991 August 22; 352(6337): 725–728. [2] Envelope-binding domain in the cationic amino acid transporter determines the host range of ecotropic murine retroviruses. Albritton LM, Kim JW, Tseng L, Cunningham JM. J Virol. 1993 Apr;67(4):2091-6.
[3] Anemia and perinatal death result from loss of the murine ecotropic retrovirus receptor mCAT-1. Perkins CP, Mar V, Shutter JR, del Castillo J, Danilenko DM, Medlock ES, Ponting IL, Graham M, Stark KL, Zuo Y, Cunningham JM, Bosselman RA. Genes Dev. 1997 Apr 1;11(7):914-25.
Sequence and Features