Hindsight regulates photoreceptor axon targeting through transcriptional control of jitterbug/Filamin and multiple genes involved in axon guidance in Drosophila. Issue 9 (18th February 2015)

• Record Type: Journal Article
• Authors: Oliva, Carlos; Molina‐Fernandez, Claudia; Maureira, Miguel; Candia, Noemi; López, Estefanía; Hassan, Bassem; Aerts, Stein; Cánovas, José; Olguín, Patricio; Sierralta, Jimena
• Is Part Of: Developmental neurobiology. Volume 75:Issue 9(2015:Sep.)
• Page Start: 1018
• Page End: 1032
• Publication Date: 2015-02-18
• Subjects: Neurobiology -- Periodicals; Neurobiology; Neurobiologie -- Périodiques; Neurobiology; Periodicals; Periodicals; 573.838
• DOI: 10.1002/dneu.22271
• Languages: English
• ISSNs: 1932-8451

Abstract

<abstract abstract-type="main"> <title>ABSTRACT</title> <p>During axon targeting, a stereotyped pattern of connectivity is achieved by the integration of intrinsic genetic programs and the response to extrinsic long and short‐range directional cues. How this coordination occurs is the subject of intense study. Transcription factors play a central role due to their ability to regulate the expression of multiple genes required to sense and respond to these cues during development. Here we show that the transcription factor HNT regulates layer‐specific photoreceptor axon targeting in <italic>Drosophila</italic> through transcriptional control of <italic>jbug/Filamin</italic> and multiple genes involved in axon guidance and cytoskeleton organization.Using a microarray analysis we identified 235 genes whose expression levels were changed by HNT overexpression in the eye primordia. We analyzed nine candidate genes involved in cytoskeleton regulation and axon guidance, six of which displayed significantly altered gene expression levels in <italic>hnt</italic> mutant retinas. Functional analysis confirmed the role of OTK/PTK7 in photoreceptor axon targeting and uncovered Tiggrin, an integrin ligand, and Jbug/Filamin, a conserved actin‐ binding protein, as new factors that participate of photoreceptor axon targeting. Moreover, we provided <italic>in silico</italic> and molecular evidence that supports <italic>jbug/Filamin</italic> as a direct transcriptional target of HNT and that HNT acts partially through Jbug/Filamin <italic>in vivo</italic> to regulate axon guidance. Our work broadens the understanding of how HNT regulates the coordinated expression of a group of genes to achieve the correct connectivity pattern in the <italic>Drosophila</italic> visual system. © 2015 Wiley Periodicals, Inc. Develop Neurobiol 75: 1018–1032, 2015</p> </abstract>