JunB overexpression in B lymphocytes is accompanied by an increased expression of the cyclin-dependent kinase inhibitor protein p16. (A) Semiquantitative RT-PCR analysis of p16 mRNA levels in lung and spleen from Ubi-junB transgenic animals and their wild-type littermate controls. (B) B- and T-lymphoid cells were MACS sorted from spleen of wild-type and Ubi-junB transgenic mice and subjected to Western blot analysis (upper panel) for JunB, p16, and β-actin (loading control). One representative FACS analysis of the purified B- and T-lymphoid cells after MACS purification is depicted (lower panel). (C) B- and T-lymphoid cells were MACS sorted from spleen of wild-type and Ubi-junB transgenic mice, stimulated with growth stimuli as indicated, and subjected to Western blot analysis for JunB, p16, and β-actin (loading control).