Programmed synthesis of collagen during postembryonic development of the nematode Panagrellus silusiae☆

[摘要] Therelativerateofcollagensynthesisinthefree-livingnematodePanagrellussilusiaeduringpostembryonicdevelopmentwasfoundtobediscontinuousbymeasuringeithertheincorporationoftritiumintomaterialextractedascollagenortheamountofcollagen-boundtritiatedprolineandhydroxyprolineafter2-hrincubationsofwholewormswith[3H]proline.Apeakofcollagenproductionprecededeachofthethreemoltsthatwereexamined.Moreover,protocollagenprolylhydroxylaseactivityduringeachintermoltperiodparalleledthepatternofcollagensynthesis.Ontheotherhand,atriphasicpatternwasnotobservedwhennoncollagenousproteinswerelabeledwitheither[3H]tryptophanor[3H]leucine.Inaddition,thelevelofsolubleradioactiveprolinethataccumulatesinwholeorganismsafter2-hrincubationperiodsdidnotfluctuateappreciablyduringpostembryonicdevelopment.Themeanratioofhydroxy-prolinetoprolineinanumberofcollagensamplesextractedatvarioustimesduringthematurationphasewas0.113±0.040.Pulseandchaseexperimentswith[3H]prolineindicatedthatmostofthecollagensynthesizedduringapeakperiodislostafterthesecondecdysisfollowingthelabelinginterval.Incontrast,aconsiderableproportionofthecollagensynthesizedduringnonpeakperiodsisretainedthroughoutthepostembryonicperiod.ItispostulatedthatthemodulatedpatternofcollagenbiosynthesisinPanagrellusreflects,forthemostpart,aquantitativeregulationoftheproductionofcuticularcollagenduringpostembryonicdevelopment.

[学科分类] 生物科学（综合）