Age-dependent changes of gene expression in the Drosophila head.
Previous gene expression profiling studies in Drosophila have provided clues for understanding the aging process at the gene expression level. For a detailed understanding, studies of specific regions of the body are necessary. We therefore employed microarray analysis to examine gene expression changes in the Drosophila head during aging. Six hundred and eighty-four of the 5405 genes present in the microarray showed significant age-dependent changes as determined by significance analysis of microarray (SAM) (q < 0.05). The biological significance of the changes was analyzed using the gene annotations provided by the Gene Ontology Consortium. Major changes involved genes affecting energy metabolism (proton transport, energy pathways, oxidative phosphorylation) and neuronal function, especially responses to light. Genes involved in protein catabolism and several other metabolic processes also showed age-dependent changes. Most of the changes were reductions in gene expression and occurred before day 13 of adult life. After day 13, the age-dependent gene expression changes were relatively smaller than earlier life. Interestingly, the two biological processes of major gene expression changes are related to the two known environmental changes that increase life span in Drosophila: caloric restriction and light reduction. Our findings suggest that light signaling and energy metabolism may be important biological processes affected by aging and be interesting targets for the further investigation related to the longevity in Drosophila.
Kim
Se Nyun
SN
Digital Genomics Inc., Seoul 120-749, South Korea.
Rhee
Ji-Hwan
JH
Song
Young-Hwa
YH
Park
Dong Yoon
DY
Hwang
Mina
M
Lee
Sung-Ll
SL
Kim
Ja Eun
JE
Gim
Byung Soo
BS
Yoon
Jeong Ho
JH
Kim
Young-Joon
YJ
Kim-Ha
Jeongsil
J
D000367:Age Factors; D000375:Aging / Q000502:physiology*; D000818:Animals; D004330:Drosophila; D015870:Gene Expression / Q000502:physiology*; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation / Q000502:physiology*; D006257:Head / Q000502:physiology*; D017403:In Situ Hybridization / Q000379:methods; D046228:Microarray Analysis / Q000379:methods