Co-suppression of Dictyostelium discoideum myosin II heavy-chain gene expression by a sense orientation transcript.
We have previously demonstrated effective inhibition of Dictyostelium discoideum myosin heavy chain (MIIHC) gene expression after introduction of an antisense gene on a transformation vector into cells. We now report that transcription of a sense orientation MIIHC gene has a similar, though not as dramatic, effect on expression from the endogenous gene. Cells transformed with a sense fragment of the MIIHC gene are defective in cytokinesis and become giant and multinucleated when growing on a surface. This morphological phenotype is correlated with decreased expression of the endogenous MIIHC gene. Sense transformants accumulate less MIIHC protein and mRNA than control transformed cells, concomitant with accumulation of a vector-derived sense transcript. Expression of the introduced sequences seems to be required for the sense effect. The possible causes of this surprising phenomenon are discussed.
Scherczinger
C A
CA
Department of Molecular and Cell Biology, University of Connecticut, Storrs.
Knecht
D A
DA
D000818:Animals; D015152:Blotting, Northern; D015153:Blotting, Western; D003001:Cloning, Molecular; D004023:Dictyostelium / Q000235:genetics*; D015870:Gene Expression; D005822:Genetic Vectors; D009218:Myosins / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics*; D014158:Transcription, Genetic; D014170:Transformation, Genetic
D012333:RNA, Messenger; D009218:Myosins