Evidence for the expression of actomyosin in the infective stage of the sporozoan protist Eimeria.
A high-speed supernatant extract was obtained from infective oocysts of Eimeria tenella homogenised in a sucrose-low ionic strength buffer. Immunoblotting showed this soluble, micropore-filtered preparation (designated E1) to be rich in actin. E1 underwent superprecipitation on addition of ATP but not its non-hydrolysable analogue AMP.PMP--behaviour typical of an actomyosin solution. The superprecipitate fluoresced strongly in the presence of rhodamine-phalloidin (indicative of the presence of F-actin) and electron microscopy of negatively-stained preparations of this flocculent matter confirmed the abundance of filamentous material within it. This is the first demonstration of a functional actomyosin isolated from a member of the economically important phylum Apicomplexa.
Preston
T M
TM
Biology Department, University College London, England.
King
C A
CA
D000199:Actins / Q000032:analysis; D000205:Actomyosin / Q000032:analysis*; D000255:Adenosine Triphosphate / Q000494:pharmacology; D000266:Adenylyl Imidodiphosphate / Q000494:pharmacology; D000818:Animals; D011232:Chemical Precipitation; D016786:Eimeria tenella / Q000737:chemistry* / Q000648:ultrastructure; D015151:Immunoblotting; D008854:Microscopy, Electron; D010590:Phalloidine; D012235:Rhodamines
D000199:Actins; D012235:Rhodamines; D010590:Phalloidine; D000266:Adenylyl Imidodiphosphate; D000255:Adenosine Triphosphate; D000205:Actomyosin