Senseless acts as a binary switch during sensory organ precursor selection

Jafar-Nejad, Hamed; Acar, Melih; Nolo, Riitta; Lacin, Haluk; Pan, Hongling; Parkhurst, Susan M.; Bellen, Hugo J.

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NASA NTRS · 20040087444

Senseless acts as a binary switch during sensory organ precursor selection

Jafar-Nejad, Hamed·Acar, Melih·Nolo, Riitta·Lacin, Haluk·Pan, Hongling·Parkhurst, Susan M.·Bellen, Hugo J.

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Abstract

During sensory organ precursor (SOP) specification, a single cell is selected from a proneural cluster of cells. Here, we present evidence that Senseless (Sens), a zinc-finger transcription factor, plays an important role in this process. We show that Sens is directly activated by proneural proteins in the presumptive SOPs and a few cells surrounding the SOP in most tissues. In the cells that express low levels of Sens, it acts in a DNA-binding-dependent manner to repress transcription of proneural genes. In the presumptive SOPs that express high levels of Sens, it acts as a transcriptional activator and synergizes with proneural proteins. We therefore propose that Sens acts as a binary switch that is fundamental to SOP selection.

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NASA Program Fundamental Space Biology NASA Discipline Developmental Biology Non-NASA Center Transcription Factors/chemistry/genetics/physiology Sense Organs/embryology/physiology Nuclear Proteins/chemistry/genetics/physiology Promoter Regions (Genetics)Sequence Homology, Amino Acid Amino Acid Sequence Animals Drosophila Proteins/genetics DNA-Binding Proteins/genetics Repressor Proteins/genetics Support, U.S. Gov't, Non-P.H.S Drosophila Molecular Sequence Data Transcription, Genetic

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Jafar-Nejad, Hamed, Acar, Melih, Nolo, Riitta, Lacin, Haluk, Pan, Hongling, Parkhurst, Susan M., Bellen, Hugo J.. 2003-12-01. Senseless acts as a binary switch during sensory organ precursor selection. https://ntrs.nasa.gov/citations/20040087444

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