A Systematic Survey of Carbonic Anhydrase mRNA Expression During Mammalian Inner Ear Development. Issue 3 (28th January 2013)

• Record Type: Journal Article
• Authors: Wu, Ling; Sagong, Borum; Choi, Jae Young; Kim, Un‐Kyung; Bok, Jinwoong
• Is Part Of: Developmental dynamics. Volume 242:Issue 3(2013:Mar.)
• Page Start: 269
• Page End: 280
• Publication Date: 2013-01-28
• Subjects: Morphogenesis -- Periodicals; Anatomy -- Periodicals; Anatomie -- Périodiques; Biologie du développement -- Périodiques; 571.833
• DOI: 10.1002/dvdy.23917
• Languages: English
• ISSNs: 1058-8388

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p> <underline>Background</underline>: Carbonic anhydrases (CAs), which catalyze CO<sub>2</sub> hydration to bicarbonate and protons, have been suggested to regulate potassium homeostasis and endocochlear potential in the mammalian cochlea. Sixteen mammalian CA isozymes are currently known. To understand the specific roles of CA isozymes in the inner ear, a systematic survey was conducted to reveal temporal and spatial expression patterns of all 16 CA isozymes during inner ear development. <underline>Results</underline>: Our quantitative reverse transcriptase‐polymerase chain reaction results showed that different tissues express unique combinations of CA isozymes. During inner ear development, transcripts of four cytosolic isozymes (<italic>Car1</italic>, <italic>Car2</italic>, <italic>Car3</italic>, and <italic>Car13</italic>), two membrane‐bound isozymes (<italic>Car12</italic> and <italic>Car14</italic>), and two CA‐related proteins (<italic>Car8</italic> and <italic>Car11</italic>) were expressed at higher levels than other isozymes. Spatial expression patterns of these isozymes within developing inner ears were determined by in situ hybridization. Each isozyme showed a unique expression pattern during development. For example, <italic>Car12</italic> and <italic>Car13</italic> expression closely overlapped with <italic>Pendrin</italic>, an anion exchanger, while <italic>Car2</italic> overlapped with Na‐K‐ATPase in type II and IV otic fibrocytes, suggesting functional relationships in the inner ear. <underline>Conclusions</underline>: The temporal and spatial expression patterns of each CA isozyme suggest unique and differential roles in inner ear development and function. <italic>Developmental Dynamics 242:269–280, 2013</italic>. © 2012 Wiley Periodicals, Inc.</p> </abstract>