4AOW, 4UG0, 4V6X, 5A2Q, 5AJ0, 5FLX1039914694ENSG00000204628ENSMUSG00000020372P63244P68040NM_006098NM_008143NP_006089NP_032169Receptor for activated C kinase 1 (RACK1), also known as guanine nucleotide-binding protein subunit beta-2-like 1 (GNB2L1), is a 35 kDa protein that in humans is encoded by the RACK1 gene.

[5] Later studies established RACK1, and its yeast homolog Asc1, as a core ribosomal protein of the eukaryotic small (40S) ribosomal subunit.

[7][8][9] Much of the function of Asc1/RACK1 appears to result from its position on the 'head' of the 40S ribosomal subunit.

[10] Asc1/RACK1 participates in several aspects of eukaryotic translation and ribosome quality control, including IRES-mediated translation,[11] non-stop decay,[12] non-functional 18S ribosomal RNA decay,[13] and frameshifting.

[14] RACK1 is positioned at the solvent-exposed surface of the 40S ribosomal subunit, where it is held in place through contacts with both the 18S rRNA and other ribosomal proteins, including uS3, uS9, and eS17.