Bhlhb5 is required for the subtype development of retinal amacrine and bipolar cells in mice. Issue 2 (13th November 2013)

• Record Type: Journal Article
• Authors: Huang, Liang; Hu, Fang; Feng, Liang; Luo, Xiong‐Jian; Liang, Guoqing; Zeng, Xiang‐Yun; Yi, Jing‐Lin; Gan, Lin
• Is Part Of: Developmental dynamics. Volume 243:Issue 2(2014:Feb.)
• Page Start: 279
• Page End: 289
• Publication Date: 2013-11-13
• Subjects: Morphogenesis -- Periodicals; Anatomy -- Periodicals; Anatomie -- Périodiques; Biologie du développement -- Périodiques; 571.833
• DOI: 10.1002/dvdy.24067
• Languages: English
• ISSNs: 1058-8388

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <underline>Background:</underline> BHLHB5, an OLIG‐related basic helix‐loop‐helix transcription factor, is required for the development of a subset of gamma‐amino butyric acid–releasing (GABAergic) amacrine cells and OFF‐cone bipolar (CB) cells in mouse retinas. In order to determine BHLHB5's functional mechanism in retinogenesis, we used the Cre‐loxP recombination system to genetically trace the lineage of BHLHB5+ cells in normal and <italic>Bhlhb5</italic>‐null retinas. The <italic>Bhlhb5</italic>‐Cre knock‐in allele was used to activate the constitutive expression of a GFP reporter in the <italic>Bhlhb5</italic>‐expressing cells, and the cell fates of <italic>Bhlhb5</italic>‐lineage cells were identified by using specific cell markers and were compared between normal and <italic>Bhlhb5</italic>‐null retinas. <underline>Results:</underline> In addition to GABAergic amacrine and OFF‐CB cells, <italic>Bhlhb5</italic> lineage cells give rise to ganglion, glycinergic amacrine, rod bipolar, ON‐bipolar, and rod photoreceptor cells during normal retinal development. Targeted deletion of <italic>Bhlhb5</italic> resulted in the loss of GABAergic amacrine, glycinergic amacrine, dopaminergic amacrine, and Type 2 OFF‐CB cells. Furthermore, in the absence of BHLHB5, a portion of <italic>Bhlhb5</italic> lineage cells switch their fate and differentiate into cholinergic amacrine cells. <underline>Conclusions:</underline> Our data reveal a broad expression pattern of <italic>Bhlhb5</italic> throughout retinogenesis and demonstrate the cell‐autonomous as well as non‐cell‐autonomous role of <italic>Bhlhb5</italic> in the specification of amacrine and bipolar subtypes. <italic>Developmental Dynamics 243:279–289, 2014</italic>. © 2013 Wiley Periodicals, Inc.</p> </abstract>