Disease relevance of RpL23A

• The C-terminal 126 amino acid residues of the RpL23a protein, encoded by exon 3 in Drosophila, and by exons 3 and 4 in Anopheles gambiae, are well conserved, and correspond to Escherichia coli RpL23 with the addition of the eukaryotic N-terminal nuclear localization sequence [1].

High impact information on RpL23A

• The predicted amino acid sequences from 109 to 269 of PBP-3 and from 184 to 312 of PBP-12 had more than 62% identities to mammalian L23a (rpl23a) and L22 (rpl22), the ribosomal proteins of the large subunit [2].
• The histone H1-like sequence in RpL23a is encoded entirely within the second exon [1].
• The N-terminal extension in mosquito RpL23a is about 100 amino acids longer than that in the Drosophila RpL23a homolog, and contains several repeated amino acid motifs [1].
• Because low complexity amino acid extensions are not common on eukaryotic ribosomal proteins, and their functions are unknown, we cloned cDNAs encoding RpL23a from Aedes albopictus and Anopheles stephensi mosquito cell lines [1].
• RpL23a proteins in Aedes and Anopheles mosquitoes are rich in lysine ( approximately 25%), alanine ( approximately 21%), and proline ( approximately 8%), have a mass of approximately 40 kDa, a pI of 11.4 to 11.5, and contain an N-terminal extension of approximately 260 amino acid residues [1].

Anatomical context of RpL23A

• Thus, Drosophila L22 and L23a might have two functions, namely the role of DNA-binding similar to histone H1 and the role of organizing the ribosome [2].

Other interactions of RpL23A

• From six independent cDNA clones isolated, we characterized two clones, PBP-3 and PBP-12 [2].
• These Drosophila ribosomal protein L22 and L23a have additional Ala-, Lys- and Pro-rich sequences at the amino terminus, which have a resemblance to the carboxy-terminal portion of histone H1 [2].

References