email: arnold@ucla.edu
phone: 310-825-2169
fax: 310-825-8081
office: 4117 LSB
homepage: http://www.physci.ucla.edu/html/arnold.htm
research interests: Sex differences in the brain, neuroendocrinology, evolution and function of the sex chromosomes
Research Interests
We study the forces that make male and female tissues different. Sexual differentiation underlies sex differences in behavior, physiology, and susceptibility to disease. Our recent research on mice indicates that genes on the sex chromosomes, X and Y genes, are expressed differently in male and female cells and induce sex differences in non-gonadal tissues. These direct genetic actions interact with effects of gonadal hormones in the two sexes. Our goal is to identify X and Y genes that contribute to sex differences in tissue function and disease, and to understand the mechanisms of their action. We also study sex chromosome dosage compensation in birds. Males have two Z chromosomes but females have one. Birds have an ineffective mechanism of dosage compensation, which is not predicted from study of mammals and other XX/XY systems. We seek to understand the epigenetic modifications of the Z chromosome that regulate gene dosage, and the evolution of dosage compensation mechanisms.
Selected Publications
Chen X, Watkins R, Delot E, Reliene R, Schiestl RH, Burgoyne PS, Arnold AP. 2008. Sex difference in neural tube defects in p53-null mice is caused by differences in the complement of X not Y genes Developmental Neurobiology 68 265-273 .
*Gioiosa L, *Chen X, Watkins R, Klanfer N, Bryant CD, Dvans CJ, Arnold AP (*co-first authors). 2008. Sex chromosome complement affects nociception in tests of acute and chronic exposure to morphine in mice Hormones and Behavior 54 124-130 .
Arnold AP, Itoh Y, Melamed E. 2008. A bird’s eye view of sex chromosome dosage compensation Annual Review of Genomics and Human Genetics in press - .
Itoh, Y., Melamed, E., Yang, X, Kampf, D., Wang, S., Yehya, N., Van Nas, A., Replogle, K., Band M.R., Clayton, D.F., Schadt, E.E., Lusis, A.J., Arnold, A.P.. 2007. Dosage compensation is less effective in birds than in mammals Jounal of Biology - .
Melamed E, Arnold AP. 2007. Regional differences in dosage compensation on the chicken Z chromosome Genome Biology 8 R202- .
Quinn JJ, Hitchcott PK, Umeda EA, Arnold AP, Taylor JR. 2007. Sex chromosome complement determines habit formation Nature Neuroscience 10 1398-1400 .
Itoh, Y., Kampf, K., Arnold, A.P.. 2006. Assignment of human X chromosome-syntenic genes to a zebra finch microchromosome by in situ hybridization of BAC clones Cytogenetic and Genome Research 112 343-344 .
Gatewood, J.D., Wills, A., Shetty, S., XU, J., Arnold, A.P., Burgoyne, P.S., Rissman, E.F.. 2006. Sex chromosome complement and gonadal sex influence aggressive and parental behaviors in mice Journal of Neuroscience 26 2335-2342 .
Yang, X., Schadt, E.E., Wang, S., Ingram-Drake, L., Arnold, A.P., Drake, T.A., Lusis, A.J.. 2006. Tissue-specific expression and regulation of sexually dimorphic genes in mice Genome Research 16 995-1004 .
Itoh, Y., Arnold, A.P.. 2005. Chromosomal polymorphism and comparative painting analysis in the zebra finch Chromosome Research 13 47-56 .