Rapid communication: localization of POU1F1 to bovine, ovine, and caprine 1q21-22.

Name of Gene Marker. POU1F1 POU domain, class 1, transcription factor 1 (PIT1, growth hormone factor 1). Species. Bos taurus, Ovis aries, Capra hircus. Source and Description of Clone. A bovine lambda genomic library (Clontech, Inc., Palo Alto, CA) was screened by using the bovine POU1F1 cDNA (kindly provided by M. Karin, University of California-San Diego). Positive recombinant phage were characterized by restriction digestion and Southern blotting analysis. Further analysis of an approximate 12,000-bp DNA fragment containing exons 3 through 6 and flanking genomic regions of the bovine POU1F1 gene included subcloning and sequencing of the exon 4 and exon 6 regions. Method of Detection. Metaphase spreads were prepared from lymphoid cells obtained from cattle, sheep, and goats (two males and two females for each species). Standard cell culture procedures were used. To generate R-banded metaphases (RBP), cells were synchronized with methotrexate (10−6 M) for 17 h followed by addition of 20 g/mL of bromodeoxyuridine (BrdU) during the late synthesis phase (DiBerardino and Iannuzzi, 1982). Standard cell harvesting and slide preparation procedures were used. For fluorescent (in situ) hybridization (FISH), the protocol outlined by Lichter et al. (1990) was followed. The 12,000-bp genomic DNA fragment of the bovine POU1F1 gene was labeled with biotin-16-dATP by nick translation. Probe was detected with FITC-conjugated avidin DCS (Vector Labs; Burlingame, CA). After propidium iodide staining, slides were mounted with an alkaline antifade p-phenylenediamine, pH 11 (PPD-11). This antifade allows the simultaneous visualization of FITC signals and the RBP chromosome banding patterns. At least 20 metaphases from each of the animals studied were analyzed. A SIT cam-