title: bantam is required for optic lobe development and glial cell proliferation.
abstract: microRNAs (miRNAs) are small, conserved, non-coding RNAs that contribute to the control of many different cellular processes, including cell fate specification and growth control. Drosophila bantam, a conserved miRNA, is involved in several functions, such as stimulating proliferation and inhibiting apoptosis in the wing disc. Here, we reported the detailed expression pattern of bantam in the developing optic lobe, and demonstrated a new, essential role in promoting proliferation of mitotic cells in the optic lobe, including stem cells and differentiated glial cells. Changes in bantam levels autonomously affected glial cell number and distribution, and non-autonomously affected photoreceptor neuron axon projection patterns. Furthermore, we showed that bantam promotes the proliferation of mitotically active glial cells and affects their distribution, largely through down regulation of the T-box transcription factor, optomotor-blind (omb, Flybase, bifid). Expression of omb can rescue the bantam phenotype, and restore the normal glial cell number and proper glial cell positioning in most Drosophila brains. These results suggest that bantam is critical for maintaining the stem cell pools in the outer proliferation center and glial precursor cell regions of the optic lobe, and that its expression in glial cells is crucial for their proliferation and distribution.
authors.affiliation: Department of Molecular Biology and Biochemistry, Cancer Institute of New Jersey, Rutgers University, Piscataway, New Jersey, United States of America.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.forename: Richard W
authors.initials: RW
authors.lastname: Padgett
mesh_terms: D000818:Animals; D001369:Axons / Q000378:metabolism; D049109:Cell Proliferation; D029721:Drosophila Proteins / Q000378:metabolism; D004331:Drosophila melanogaster / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D018507:Gene Expression Regulation, Developmental; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009457:Neuroglia / Q000166:cytology* / Q000378:metabolism; D009899:Optic Lobe, Nonmammalian / Q000166:cytology / Q000254:growth & development* / Q000378:metabolism; D010786:Photoreceptor Cells / Q000378:metabolism; D020825:T-Box Domain Proteins / Q000378:metabolism
chemical_list: D029721:Drosophila Proteins; D035683:MicroRNAs; D009419:Nerve Tissue Proteins; D020825:T-Box Domain Proteins; C471146:bantam microRNA, Drosophila; C072962:bi protein, Drosophila