Leucine aminopeptidase during meiotic development.
We found a leucine aminopeptidase (LAP; EC 3.4.11.1) to be abundant in meiotic prophase tissue of a basidiomycete, Coprinus cinereus. After direct purification of the aminopeptidase component from meiocytes, we cloned the gene by degenerate PCR using partial amino-acid sequences of the purified enzyme and 5' and 3' RACE. It was homologous to the eukaryotic leucine aminopeptidase gene. The recombinant protein possesses the characteristic activities of a Coprinus leucine aminopeptidase (CoLAP) with a molecular mass of 52.4 kDa, and forms a homohexamer. Northern blot and spatial distribution analysis by immunohistochemical staining indicated CoLAP to be abundant in meiotic prophase cells and the supporting cells around meiocytes, but scarce in mycelium cells. Interestingly, from zygotene to pachytene, CoLAP was mostly present in supporting cells around meiocytes, but from diplotene onwards, it was plentiful in meiocytes themselves, suggesting that its expression is required to control some of the biochemical events at meiotic prophase. Moreover, the strong expression of CoLAP mRNA immediately after treatment with methyl methanesulfonate in mycelium implies that CoLAP has a role in somatic DNA repair.
Ishizaki
Takashi
T
Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
Tosaka
Aki
A
Nara
Takayuki
T
Aoshima
Narumichi
N
Namekawa
Satoshi
S
Watanabe
Kei
K
Hamada
Fumika
F
Omori
Akira
A
Sakaguchi
Kengo
K
D000595:Amino Acid Sequence; D001483:Base Sequence; D015152:Blotting, Northern; D003302:Coprinus / Q000235:genetics* / Q000378:metabolism; D007150:Immunohistochemistry; D007931:Leucyl Aminopeptidase / Q000235:genetics* / Q000302:isolation & purification / Q000378:metabolism*; D008540:Meiosis; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism
D011994:Recombinant Proteins; D007931:Leucyl Aminopeptidase