Ribosomal proteins expression and phylogeny in alpaca (Lama pacos) skin

Ribosomal proteins (RP) has been reported as a central player in the translation system, and are required for the growth and maintenance of all cell kinds. RP genes form a family of homologous proteins that express in the stable pattern and were used for phylogenetic analysis. Here we constructed a cDNA library of alpaca skin and 13,800 clones were sequenced. In the cDNA library, RP genes from skin cDNA library of alpaca were identified. Then 8 RP genes were selected at random and built the phylogenetic trees from the DNA sequences by using parsimony or maximum likelihood methods for molecular and evolutionary analysis of ribosomal proteins. The results showed that the 42 RP genes of alpaca have been expressed in alpaca skin. They were highly conserved. The phylogeny inferred from all these methods suggested that the evolutionary distances of alpaca RP genes were closer to rat.