A systems biology approach to the identification and analysis of transcriptional regulatory networks in osteocytes.
BACKGROUND
The osteocyte is a type of cell that appears to be one of the key endocrine regulators of bone metabolism and a key responder to initiate bone formation and remodeling. Identifying the regulatory networks in osteocytes may lead to new therapies for osteoporosis and loss of bone.


RESULTS
Using microarray, we identified 269 genes over-expressed in osteocyte, many of which have known functions in bone and muscle differentiation and contractility. We determined the evolutionarily conserved and enriched TF binding sites in the 5 kb promoter regions of these genes. Using this data, a transcriptional regulatory network was constructed and subsequently partitioned to identify cis-regulatory modules.


CONCLUSIONS
Our results show that many osteocyte-specific genes, including two well-known osteocyte markers DMP1 and Sost, have highly conserved clustering of muscle-related cis-regulatory modules, thus supporting the concept that a muscle-related gene network is important in osteocyte biology and may play a role in contractility and dynamic movements of the osteocyte.
Dean
Angela K
AK
Department of Computer Science, The University of Texas at San Antonio, San Antonio, TX 78249, USA. adean@cs.utsa.edu
Harris
Stephen E
SE
Kalajzic
Ivo
I
Ruan
Jianhua
J
D002454:Cell Differentiation; D019295:Computational Biology / Q000379:methods*; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods; D010011:Osteocytes / Q000378:metabolism*; D049490:Systems Biology / Q000379:methods*