title: Notch signaling downstream target E(spl)mbeta is dispensable for adult midgut homeostasis in Drosophila.
abstract: Adult tissue homeostasis is maintained by residential stem cells through the proper balance of stem cell self-renewal and differentiation. The adult midgut of Drosophila contains multipotent intestinal stem cells (ISCs), and Notch signaling plays critical roles in the proliferation and differentiation of these ISCs. However, how Notch signaling downstream targets regulate ISC proliferation and differentiation still remains unclear. Here we find that Notch signaling downstream targets E(spl)mbeta and E(spl)malpha are differentially expressed in ISCs and their progeny. Interestingly, we find that midgut homeostasis is not affected in E(spl)mbeta null mutant. No obvious defects are observed in the intestines ectopically expressing E(spl)mbeta or E(spl)malpha. Importantly, we find that the defects in ISC proliferation and differentiation observed in Notch mutant cannot be rescued by ectopic expression of E(spl)mbeta or E(spl)malpha. Together, these data indicate that the proliferation and differentiation of ISCs are not regulated by individual Notch downstream target, but by different downstream targets collectively.
authors: Plant Science and Technology College, Beijing University of Agriculture, Beijing 102206, China; Beijing Key Laboratory of New Technology in Agriculture Application, Beijing University of Agriculture, Beijing 102206, China. Electronic address: luyf2013@bua.edu.cn.
authors: Yanfen
authors: Y
authors: Lu
authors: School of Life Sciences, Capital Normal University, Beijing 100048, China. Electronic address: zhli@cnu.edu.cn.
authors: Zhouhua
authors: Z
authors: Li
mesh_terms: D053687:Adult Stem Cells / Q000502:physiology; D000818:Animals; D030801:Animals, Genetically Modified; D051792:Basic Helix-Loop-Helix Proteins / Q000235:genetics / Q000502:physiology*; D002454:Cell Differentiation / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D029721:Drosophila Proteins / Q000235:genetics / Q000502:physiology*; D004331:Drosophila melanogaster / Q000235:genetics / Q000502:physiology; D005786:Gene Expression Regulation; D006706:Homeostasis / Q000235:genetics*; D007422:Intestines / Q000166:cytology / Q000502:physiology*; D039902:Multipotent Stem Cells / Q000502:physiology*; D051880:Receptors, Notch / Q000502:physiology; D015398:Signal Transduction / Q000235:genetics
chemical_list: D051792:Basic Helix-Loop-Helix Proteins; D029721:Drosophila Proteins; D051880:Receptors, Notch; C497759:N protein, Drosophila; C077963:E(spl)mbeta-HLH protein, Drosophila
keywords: Drosophila; E(spl)mbeta; Midgut; Notch signaling; Stem cell