Beacon/ubiquitin-like 5-immunoreactivity in the hypothalamus and pituitary of the mouse.
Beacon is a 73-amino acid peptide encoded by a novel gene in the hypothalamus of Israeli sand rat Psammomys obesus. Reverse transcriptase polymerase chain reaction (RT-PCR) and immunohistochemical techniques were used to investigate the presence of beacon mRNA and the distribution of beacon-immunoreactivity (irBC) in the hypothalamus of ICR mice. RT-PCR experiments revealed beacon mRNA in the mouse hypothalamus. Using a rabbit polyclonal antiserum directed against the synthetic C-terminal peptide fragment (47-73), irBC was detected in the mouse hypothalamus and pituitary. In the hypothalamus, irBC was concentrated in perikarya of the supraoptic (SO), paraventricular (PVH) and accessory neurosecretory nuclei and in cell processes of the median eminence and pituitary stalk. In the pituitary, irBC was noted mainly in the posterior lobe. Double-labeling the hypothalamic sections with guinea-pig vasopressin-antiserum or mouse monoclonal oxytocin-antibody and beacon-antiserum revealed that <30% of vasopressin-immunoreactive neurons and nearly all oxytocin-immunoreactive neurons in the PVH and SO were irBC. The result shows the presence of beacon mRNA in the mouse hypothalamus, and the distribution of irBC is distinctively different from that reported in the hypothalamus of Psammomys obesus, but similar to that of the Sprague-Dawley rats described in our earlier study. More interestingly, Blast search uncovered a 73-amino acid peptide, human ubiquitin-like 5, which has the same exact sequence as beacon. Thus, irBC observed in the mouse brain could be that of ubiquitin-like 5.
Brailoiu
G Cristina
GC
Department of Pharmacology, James H. Quillen College of Medicine, East Tennessee State University, P.O. Box 70577, Johnson City, TN 37614, USA. dunnae@mail.etsu.edu
Dun
Siok L
SL
Chi
Michelle
M
Ohsawa
Masahiro
M
Chang
Jaw Kang
JK
Yang
Jun
J
Dun
Nae J
NJ
D000818:Animals; D005136:Eye Proteins / Q000032:analysis* / Q000096:biosynthesis; D005260:Female; D006801:Humans; D007031:Hypothalamus / Q000737:chemistry* / Q000378:metabolism; D007150:Immunohistochemistry; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000096:biosynthesis; D010902:Pituitary Gland / Q000737:chemistry* / Q000378:metabolism; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D014452:Ubiquitins / Q000032:analysis* / Q000096:biosynthesis
D005136:Eye Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; C429294:UBL5 protein, human; D014452:Ubiquitins; C485936:Ubl5 protein, mouse