02515nas a2200289   4500008004100000245007500041210006900116300001200185490000800197520143200205653002101637653001201658653007101670653010001741653010001841100002301941700001401964700001501978700001801993700002202011700002002033700001602053700001702069700001302086700002002099856010602119       2008                        eng d00aTranscriptional profiling of mRNA expression in the mouse distal colon0 aTranscriptional profiling of mRNA expression in the mouse distal  a2019-290 v1353 aBACKGROUND & AIMS: Intestinal epithelial cells and the myenteric plexus of the mouse gastrointestinal tract contain a circadian clock-based intrinsic time-keeping system. Because disruption of the biological clock has been associated with increased susceptibility to colon cancer and gastrointestinal symptoms, we aimed to identify rhythmically expressed genes in the mouse distal colon. METHODS: Microarray analysis was used to identify genes that were rhythmically expressed over a 24-hour light/dark cycle. The transcripts were then classified according to expression pattern, function, and association with physiologic and pathophysiologic processes of the colon. RESULTS: A circadian gene expression pattern was detected in approximately 3.7% of distal colonic genes. A large percentage of these genes were involved in cell signaling, differentiation, and proliferation and cell death. Of all the rhythmically expressed genes in the mouse colon, approximately 7% (64/906) have been associated with colorectal cancer formation (eg, B-cell leukemia/lymphoma-2 [Bcl2]) and 1.8% (18/906) with various colonic functions such as motility and secretion (eg, vasoactive intestinal polypeptide, cystic fibrosis transmembrane conductance regulator). CONCLUSIONS: A subset of genes in the murine colon follows a rhythmic expression pattern. These findings may have significant implications for colonic physiology and pathophysiology.10aAnimals Blotting10aGenetic10aInbred C57BL Microarray Analysis Proteins/*genetics/metabolism RNA10aMessenger/biosynthesis/*genetics Reverse Transcriptase Polymerase Chain Reaction *Transcription10aWestern Cell Proliferation Circadian Rhythm/*genetics Colon/cytology/*metabolism Male Mice Mice1 aHoogerwerf, W., A.1 aSinha, M.1 aConesa, A.1 aLuxon, B., A.1 aShahinian, V., B.1 aCornelissen, G.1 aHalberg, F.1 aBostwick, J.1 aTimm, J.1 aCassone, V., M.  uhttp://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=18848557