Loss of PTB or negative regulation of Notch mRNA reveals distinct zones of Notch and actin protein accumulation in Drosophila embryo

• Published in: PloS one 2011-07, Vol.6 (7), p.e21876-e21876
• Main Authors: Wesley, Cedric S, Guo, Heng, Chaudhry, Kanita A, Thali, Markus J, Yin, Jerry C, Clason, Todd, Wesley, Umadevi V
• Format: Article
• Language: English
• Subjects: Actin; Actins - genetics; Actins - metabolism; Animals; Apoptosis - genetics; Biochemistry; Biology; Blotting, Northern; Cell adhesion; Cell Adhesion - genetics; Cell fate; Cell Fusion; Cell Line; Cell surface; Cloning; Developmental stages; Down-regulation; Drosophila; Drosophila melanogaster - embryology; Drosophila melanogaster - genetics; Drosophila melanogaster - metabolism; Drosophila Proteins - genetics; Drosophila Proteins - metabolism; Embryo; Embryo, Nonmammalian - embryology; Embryo, Nonmammalian - metabolism; Embryogenesis; Embryonic development; Embryonic growth stage; Embryos; Gene Expression Regulation, Developmental; Genetic screening; Genetic testing; Genetics; Heart - embryology; Insects; Ligands; Messenger RNA; mRNA; mRNA processing; Muscle proteins; Mutation; Myocardium - metabolism; Nervous system; Neurosciences; Notch protein; Polypyrimidine Tract-Binding Protein - genetics; Polypyrimidine Tract-Binding Protein - metabolism; Protein binding; Proteins; Receptors, Notch - genetics; Receptors, Notch - metabolism; RNA, Messenger - genetics; RNA, Messenger - metabolism; Signal Transduction - genetics; Studies; Translation (Genetics)
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0021876

Polypyrimidine Tract Binding (PTB) protein is a regulator of mRNA processing and translation. Genetic screens and studies of wing and bristle development during the post-embryonic stages of Drosophila suggest that it is a negative regulator of the Notch pathway. How PTB regulates the Notch pathway is unknown. Our studies of Drosophila embryogenesis indicate that (1) the Notch mRNA is a potential target of PTB, (2) PTB and Notch functions in the dorso-lateral regions of the Drosophila embryo are linked to actin regulation but not their functions in the ventral region, and (3) the actin-related Notch activity in the dorso-lateral regions might require a Notch activity at or near the cell surface that is different from the nuclear Notch activity involved in cell fate specification in the ventral region. These data raise the possibility that the Drosophila embryo is divided into zones of different PTB and Notch activities based on whether or not they are linked to actin regulation. They also provide clues to the almost forgotten role of Notch in cell adhesion and reveal a role for the Notch pathway in cell fusions.