Gender-specific modulation of CNS transcriptomes by age and diet. (a) Numbers of genes that are differentially expressed in males and females in an age-dependent manner. (b) Genes differentially affected by CR in males and females. (c) Gene cluster analysis comparison of the effects of CR on hippocampal transcriptomes of male and female mice of different ages. Note the similarities in responses of young and middle-aged male and female mice, and the striking differential response of males and females to CR in old mice. (d) Age-responsive genes that were reverted by CR in males compared to females. Gene lists are in Tables S5a-d in Additional data file 1.