Protein Family Models

This model discriminates eubacterial (and mitochondrial) translation initiation factor 2 (IF-2), encoded by the infB gene in bacteria, from similar proteins in the Archaea and Eukaryotes. In the bacteria and in organelles, the initiator tRNA is charged with N-formyl-Met instead of Met. This translation factor acts in delivering the initiator tRNA to the ribosome. It is one of a number of GTP-binding translation factors recognized by the pfam HMM GTP_EFTU. A shorter form, translated from an alternative start codon more than a hundred codons downstream, is described is IF-2 beta. This model describes the long form, IF-2 alpha.

Gene:

infB

Date:

2024-05-30

Proteins with a small GTP-binding domain recognized by this model include Ras, RhoA, Rab11, translation elongation factor G, translation initiation factor IF-2, tetratcycline resistance protein TetM, CDC42, Era, ADP-ribosylation factors, tdhF, and many others. In some proteins the domain occurs more than once. This model recognizes a large number of small GTP-binding proteins and related domains in larger proteins. Note that the alpha chains of heterotrimeric G proteins are larger proteins in which the NKXD motif is separated from the GxxxxGK[ST] motif (P-loop) by a long insert and are not easily detected by this model.

Date:

2022-03-28