Selective modulation of specific protein kinase C (PKC) isoforms in primary human megakaryocytic vs. erythroid cells

✍ Scribed by Marchisio, Marco ;Bertagnolo, Valeria ;Celeghini, Claudio ;Vitale, Marco ;Capitani, Silvano ;Zauli, Giorgio

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 377 KB
• Volume: 255
• Category: Article
• ISSN: 0003-276X
• DOI: 10.1002/(sici)1097-0185(19990501)255:1<7::aid-ar2>3.0.co;2-t

✦ Synopsis

We have investigated the pattern of expression of classical (␣, ␤I, ␤II, ␥), novel (␦) and atypical () protein kinase C (PKC) isoforms during the course of human hematopoietic differentiation along the closely related megakaryocytic and erythroid lineages. Using in situ immunofluorescence analysis, freshly isolated human pluripotent CD34 ϩ hematopoietic progenitor cells expressed detectable amounts of all the PKC isoforms investigated. On the other hand, clear-cut differences in terms of PKC staining were noticed between cells belonging to the erythroid and megakaryocytic lineages, obtained after 9 days of serum-free liquid culture in the presence of specific growth factors. Specifically, 1) erythroid cells showed a very weak expression of PKC-␣, -␤I, -␤II, and -␥, while megakaryocytes showed an enhanced expression of all classical PKC isoforms, predominantly confined to the cytoplasm; 2) the expression of PKC-␦ increased in the cytoplasmic and nuclear compartments of both erythroid and megakaryocytic cells with respect to CD34 ϩ cells; and 3) atypical PKC-isoform showed a striking accumulation in the nucleus during both erythroid and megakaryocytic