Biochemical research on oogenesis: Oocytes and liver cells of the teleost fish Tinca tinca contain different kinds of 5S RNA☆

[摘要] PrevitellogenicoocytesofTincatincaaccumulateverylargeamountsof5SRNA.Weshowherethat5SRNAstoredinoocytesdiffersfromliver5SRNAin3outof120nucleotides.Liverandoocyte5SRNAs,therefore,areproducedbydifferentgenes.Bothkindsof5Sgenesareactiveinoocytes.However,only5SRNAoftheoocytetypeaccumulatesinthesecells.InTincatincaasinXenopuslaevis,oocyte-typeandsomatic-type5SRNAsdifferbythreeproperties,ie.,primarystructure,conformation,andmetabolicstability.Nucleotidesubstitutionsoccurindifferentpositionsinoocyteandsomatic5SRNAsofTincatincaandXenopuslaevis.Wedonotunderstandhowdifferentsetsofnucleotidesubstitutionsconferto5SRNAsofbothspeciessimilarpropertiesinvivo,namely,increasedmetabolicstability.

[学科分类] 生物科学（综合）