GATA-1 mRNA alternative splicing in human and murine tissues. (A) Reverse transcription–polymerase chain reaction (RT-PCR) of cDNA from human bone marrow, cord blood, and second-trimester (15 weeks) fetal blood, liver, and bone marrow, the expected size of the exon 1/2/3 splice variant (348 bp) and an exon 1/3 splice variant (109 bp) are marked. (B) RT-PCR of cDNA from murine hematopoietic tissues and the erythroleukemia cell line MEL. The expected size of an exon 1/2/3 splice variant (356 bp) and an exon 1/3 splice variant (117 bp) are marked. (C) Western blot of a MEL nuclear extract using M20 GATA-1 antibody (Santa Cruz Biotechnology), the predicted size of GATA-1FL is 47 kDa and GATA-1s 40 kDa.