Molecular and biochemical study of the presence and synthesis sites of methionine enkephalin-like substances in the circumoesophageal ganglia, the ovotestis and the tentacles of the snail.
In situ hybridization with an oligonucleotidic 35S-labelled probe complementary to the 388-435 coding region of rat proenkephalin mRNA seems to show a colocalization between synthesis and storage sites of methionine-enkephalin(MK)-like substances only in young cellular stages of the ovotestis and in several neurons of cerebral, parietal and pleural ganglia. No positive signal can be detected neither in pedal and visceral ganglia nor in the tentacular collar cells, in spite of previous immunocytochemical data. Radioimmunoassays carried out on acidic extracts of the same organs confirm the molecular results and lead us to conclude to the presence of substances strongly related to MK in the ovotestis as well as in the circumoesophageal ganglia (COG), and to ascertain that the MK-positive tentacular collar cells do not contain authentic MK.
Magdelaine
S
S
Laboratoire de Zoologie et Embryologie, Faculté des Sciences, Besançon, France.
Baltzer
F
F
Baud
C
C
Marchand
C R
CR
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D004744:Enkephalin, Methionine / Q000032:analysis*; D005724:Ganglia / Q000737:chemistry; D006066:Gonads / Q000737:chemistry; D006372:Helix, Snails / Q000033:anatomy & histology* / Q000737:chemistry; D008969:Molecular Sequence Data; D009693:Nucleic Acid Hybridization; D011863:Radioimmunoassay
D004744:Enkephalin, Methionine