Senseless acts as a binary switch during sensory organ precursor selection.

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

doi:10.1101/gad.1122403

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Senseless acts as a binary switch during sensory organ precursor selection.

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

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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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Amino Acid Sequence Animals Basic Helix-Loop-Helix Proteins DNA-Binding Proteins Drosophila Drosophila Proteins Molecular Sequence Data Nuclear Proteins Promoter Regions, Genetic Repressor Proteins Sense Organs Sequence Homology, Amino Acid Transcription Factors Transcription, Genetic NASA Discipline Developmental Biology NASA Program Fundamental Space Biology Non-NASA Center Journal Article Research Support, U.S. Gov't, Non-P.H.S.

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Hamed Jafar-Nejad, Melih Acar, Riitta Nolo, Haluk Lacin, Hongling Pan, Susan M Parkhurst, Hugo J Bellen. 2003-12-01. Senseless acts as a binary switch during sensory organ precursor selection.. https://doi.org/10.1101/gad.1122403

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