The gene encoding ribosomal protein S19 (RPS19) has been shown to be mutated in 
25% of the patients affected by Diamond-Blackfan anemia (DBA), a congenital 
erythroblastopenia. As the role of RPS19 in erythropoiesis is still to be 
defined, we performed studies on RPS19 expression during terminal erythroid 
differentiation. Comparative analysis of the genomic sequences of human and 
mouse RPS19 genes enabled the identification of 4 conserved sequence elements in 
the 5' region. Characterization of transcriptional elements allowed the 
identification of the promoter in the human RPS19 gene and the localization of a 
strong regulatory element in the third conserved sequence element. By Northern 
blot and Western blot analyses of murine splenic erythroblasts infected with the 
anemia-inducing strain Friend virus (FAV cells), RPS19 mRNA and protein 
expression were shown to decrease during terminal erythroid differentiation. We 
anticipate that these findings will contribute to further development of our 
understanding of the contribution of RPS19 to erythropoiesis.