JAK/STAT and the GATA factor Pannier control hemocyte maturation and differentiation in Drosophila

• Published in: Developmental biology 2011-04, Vol.352 (2), p.308-316
• Main Authors: Minakhina, Svetlana, Tan, William, Steward, Ruth
• Format: Article
• Language: English
• Subjects: Animals; Animals, Genetically Modified; Cell Differentiation - genetics; Cell Differentiation - physiology; Drosophila; Drosophila - genetics; Drosophila - growth & development; Drosophila - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; GATA factor; Gene Expression Regulation, Developmental; Genes, Insect; Hematopoiesis; Hematopoiesis - genetics; Hematopoiesis - physiology; Hemocytes - cytology; Hemocytes - metabolism; JAK/STAT; Janus Kinases - genetics; Janus Kinases - metabolism; Pnr; RNA Interference; Signal Transduction; STAT Transcription Factors - genetics; STAT Transcription Factors - metabolism; Transcription Factors - genetics; Transcription Factors - metabolism
• ISSN: 0012-1606; 1095-564X
• DOI: 10.1016/j.ydbio.2011.01.035

The lymph gland is the major site of hematopoiesis in Drosophila. During late larval stages three types of hemocytes are produced, plasmatocytes, crystal cells, and lamellocytes, and their differentiation is tightly controlled by conserved factors and signaling pathways. JAK/STAT is one of these pathways which have essential roles in vertebrate and fly hematopoiesis. We show that Stat has opposing cell-autonomous and non-autonomous functions in hemocyte differentiation. Using a clonal approach we established that loss of Stat in a set of prohemocytes in the cortical zone induces plasmatocyte maturation in adjacent hemocytes. Hemocytes lacking Stat fail to differentiate into plasmatocytes, indicating that Stat positively and cell-autonomously controls plasmatocyte differentiation. We also identified the GATA factor pannier (pnr) as a downstream target of Stat. By analyzing the phenotypes resulting from clonal loss and over-expression of pnr in lymph glands, we find that Pnr is positively regulated by Stat and specifically required for the differentiation of plasmatocytes. Stat and Pnr represent two essential factors controlling blood cell maturation in the developing lymph gland and exert their functions both in a cell-autonomous and non-cell-autonomous manner. ► Stat has a non-cell autonomous and autonomous functions in hematopoiesis. ► Stat negatively regulates the hemocyte maturation program non-cell autonomously. ► Stat is required cell-autonomously for plasmatocyte differentiation. ► The GATA factor Pnr is downstream of STAT. ► Pnr is also essential for plasmatocyte differentiation.