Interaction of N1-substituted adenines with 1-methyladenine receptors of starfish oocytes in induction of maturation.
Starfish oocytes are arrested naturally in the late G(2) phase of the first meiotic division. In response to the natural maturation-inducing hormone, 1-methyladenine (1-MA), oocytes undergo reinitiation of meiosis with germinal vesicle breakdown. We tested 10 newly synthesized N1-substituted adenines that are 1-MA analogues to analyze the interaction between 1-MA and its stereo-specific receptors on the oocyte plasma membranes of the starfish Asterina pectinifera. Among these analogues, 1-(beta-naphthylmethyl)adenine, 1-aminoadenine and 1-(p-nitrobenzyl)adenine played agonistic roles in the induction of oocyte maturation. 1-(o-Nitrobenzyl)adenine, 1-(m-nitrobenzyl)adenine, 1-phenethyladenine and 1-(p-nitrophenethyl)adenine had antagonist effects on 1-MA-induced oocyte maturation. These agonists and antagonists behaved competitively in the binding of [3H]1-MA to receptors in oocyte cortices. In contrast, 1-(alpha-naphthylmethyl)adenine, 1-(2,4-dinitrobenzyl)adenine and 1-(p-methoxybenzyl)adenine had no effects on oocyte maturation. Our results suggest that regional-specific sterical structures at the N1-site of adenine are important in the interaction between 1-MA and its receptors in oocytes. In addition, a negative charge at the N1-site of adenine is required for binding with the receptors.
Mita
M
M
Teikyo Junior College, 6-31-1 Honmachi, Shibuya-ku, 151-0092, Tokyo, Japan. bio-mita@lycos.ne.jp
Yoshikuni
M
M
Nagahama
Y
Y
Maekawa
M
M
Saito
M
M
Saneyoshi
M
M
D000225:Adenine / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D000818:Animals; D001667:Binding, Competitive; D004305:Dose-Response Relationship, Drug; D009865:Oocytes / Q000187:drug effects* / Q000254:growth & development*; D009866:Oogenesis / Q000187:drug effects*; D011485:Protein Binding; D011956:Receptors, Cell Surface / Q000378:metabolism*; D043562:Receptors, G-Protein-Coupled; D013215:Starfish; D013237:Stereoisomerism
C064996:1-methyladenine receptor; D011956:Receptors, Cell Surface; D043562:Receptors, G-Protein-Coupled; D000225:Adenine