Title Evolution of the myoglobin gene in Antarctic icefishes (Channichthyidae)
Author Borley, K.A.; Sidell, B.D.
Author Affil Borley, K.A., University of Maine, Department of Molecular and Biomedical Sciences, Orono, ME
Source Polar Biology, 34(5), p.659-665. Publisher: Springer-Verlag, Berlin, Germany. ISSN: 0722-4060
Publication Date May 2011
Notes In English. Supplemental information/data is available in the online version of this article; NSF grants ANT- 0437887 and ANT-0739637. 21 refs. GeoRef Acc. No: 309885
Index Terms Southern Ocean; behavior; biologic evolution; Chordata; ecology; genetics; habitat; organic compounds; physiology; Pisces; proteins; salinity; temperature; Vertebrata
Abstract Antarctic icefishes (Family: Channichthyidae) are the only adult vertebrate animals that do not express the circulatory oxygen-binding protein, hemoglobin. Six species of icefishes, including Dacodraco hunteri, also do not express myoglobin (Mb), an oxygen-binding protein found in ventricular tissue of Antarctic notothenioids. Sequence of the Mb gene from D. hunteri contains a duplicated TATA box in the promoter region of the Mb gene that is absent in Chionodraco rastrospinosus, an icefish species known to express Mb. The 15-base pair insertion in D. hunteri is identical to the duplicated TATA box that is thought to be directly responsible for preventing transcription of the Mb gene in C. aceratus, another icefish species that lacks Mb expression. Sequencing of the Mb promoter from the remaining channichthyid species revealed the duplicated TATA box in 14 of 16 icefish species, including 8 species known to express Mb. Based on the presence of the duplicated TATA box in promoters of both Mb-expressing and Mb- lacking species, loss of Mb expression in D. hunteri and C. aceratus is either independent of the duplicated TATA box, or the duplicated TATA box requires presence or absence of a distant regulatory element to prevent transcription.
URL http://hdl.handle.net/10.1007/s00300-010-0921-x
Publication Type journal article
Record ID 91540