IDENTIFICATION OF ALTERED GENE-EXPRESSION IN SKELETAL-MUSCLE DURING SEPSIS USING DIFFERENTIAL DISPLAY

Different aspects of muscle metabolism are altered during sepsis and t here is evidence that some of these changes may be regulated at the ge ne level, Differential display is a recently described technique to id entify genes whose expression has changed during a biological process, This technique utilizes reverse transcriptase-polymerase chain reacti on (RT-PCR) to compare mRNA signals in tissues during two different co nditions, We used differential display to test the hypothesis that gen e expression is altered in skeletal muscle during sepsis. Sepsis was i nduced in rats by cecal ligation and puncture (CLP). Control rats were sham-operated. Sixteen hours after CLP or sham operation, extensor di gitorum longus muscles were harvested and RNA was extracted. Following differential display, 30 fragments (F1-F30) were identified that appe ared to be uniquely expressed in muscles from sham-operated or septic rats, These fragments were reamplified by PCR and used as probes in No rthern blot analysis. Messenger RNA levels corresponding to 2 of the 3 0 fragments (F5 and F24) were confirmed to be increased by Northern bl ot analysis in septic muscle. Following cloning and sequencing, F5 was found to display significant homology to the gene sequence of the gua nine nucleotide releasing protein MSS4. The sequence of F24 did not ma tch any reported gene sequence and may therefore represent a previousl y unidentified gene. The results support the hypothesis that gene expr ession is altered in skeletal muscle during sepsis. (C) 1996 Academic Press, Inc.