title: Leucine aminopeptidase during meiotic development.
abstract: 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.
authors.affiliation: Department of Applied Biological Science, Faculty of Science and Technology, Tokyo University of Science, Noda, Chiba, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ishizaki
authors.forename: Aki
authors.initials: A
authors.lastname: Tosaka
authors.forename: Takayuki
authors.initials: T
authors.lastname: Nara
authors.forename: Narumichi
authors.initials: N
authors.lastname: Aoshima
authors.forename: Satoshi
authors.initials: S
authors.lastname: Namekawa
authors.forename: Kei
authors.initials: K
authors.lastname: Watanabe
authors.forename: Fumika
authors.initials: F
authors.lastname: Hamada
authors.forename: Akira
authors.initials: A
authors.lastname: Omori
authors.forename: Kengo
authors.initials: K
authors.lastname: Sakaguchi
mesh_terms: 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
chemical_list: D011994:Recombinant Proteins; D007931:Leucyl Aminopeptidase