Microarray analysis of differentially expressed genes in mouse bone marrow tissues after ionizing radiation.
OBJECTIVE
To identify differentially expressed genes in mouse bone marrow involved in radiation-induced injury.


METHODS
Microarray analysis was used to identify the differentially expressed genes and other techniques, e.g., polymerase chain reaction (PCR), western-blotting and antisense were also used to validate the results.


RESULTS
DNA microarray analysis demonstrated that the mRNA of 34 genes increased and 69 genes decreased in mouse bone marrow cells (BMC) from C57BL mice 6 h after a whole body dose of 6.5 Gy. These differentially expressed genes were involved in a number of processes including DNA replication/repair, proliferation/apoptosis, cell cycle control and RNA processing. In these experiments, a decline of the mammalian homolog Sir2a (an acronym for the silent mating type information regulation 2 homolog [SIRT1]) mRNA accompanied by an increase of P53 protein acetylation was observed in irradiated BMC. To determine whether the reduced SIRT1 is related to the higher acetylation status of P53 after irradiation, we designed and synthesized antisense oligonucleotides (AS) targeting human SIRT1 mRNA. Notably, AS transfection increased tumor protein 53 (P53) protein acetylation and bax-luciferase activity in human bone marrow stromal cell line (HS-5) after radiation. Furthermore, the AS transfer stimulated cell apoptosis in post-irradiation HS-5 cells.


CONCLUSIONS
Ionizing radiation (IR) affects the expression of a series of genes including genes involved in G1/S transition and the P53 pathway. Among those, reduction of SIRT1 was seen to be involved in transactivation of P53.
Dai
Jin Ming
JM
Beijing Institute of Radiation Medicine, Beijing, China.
Sun
Dao Chun
DC
Lin
Ru Xian
RX
Yang
Jing
J
Lou
Shaoke
S
Wang
Sheng Qi
SQ
D000818:Animals; D001853:Bone Marrow / Q000378:metabolism* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005260:Female; D015870:Gene Expression / Q000502:physiology / Q000528:radiation effects*; D020869:Gene Expression Profiling / Q000379:methods*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D020543:Proteome / Q000378:metabolism*; D011829:Radiation Dosage; D011839:Radiation, Ionizing
D020543:Proteome