Canastar Andrew, Maxson Stephen C, Bishop Colin E
Biobehavioral Sciences Graduate Degree Program, Department of Psychology, University of Connecticut, Storrs, CT 06269, USA.
Arch Sex Behav. 2008 Feb;37(1):2-8. doi: 10.1007/s10508-007-9257-1.
Aggressive and mating behaviors were assessed in XX females, XY females, and XY males of the C57BL/6/J/Ei ("C57BL/6" or "B6") strain of mouse. The Y chromosome of the XY females derives from Mus domesticus poschiavinus and the Y chromosome of the XY males derives from Mus musculus. The poschiavinus Y in the C57BL/6 background results in XY mice with either ovaries or ovotestes. Only those with ovaries were tested. These XY females appear to be endocrinologically identical to XX females. Aggressive and mating behaviors were also tested in XX males and XY males of the FVB/NtacfBR Odsex ("FVB") strain of mouse. The XX males have a transgene inserted 1 Mb upstream of the SOX9 gene, resulting in gonadal differentiation as a testis in the absence of a Y chromosome. C57BL/6 mice were tested for aggression in an instigated resident intruder paradigm and FVB/NtacfBR Odsex mice were tested for aggression in a neutral cage paradigm. Mice of both strains were tested with opponents of the same sex chromosome complement and gonadal sex. On the C57BL/6 background, the XY males were more aggressive than the XY and XX females, but there was no significant difference between the XX and XY females in aggression. On the FVB background, the XY and XX males were equally aggressive. Mice from both C57BL/6 and FVB backgrounds were tested for mating behaviors with females in hormonal estrus. On the C57BL/6 background, the XY males mounted more than the XY females, but there was no significant difference between the XY and XX females in mounting. On the FVB background, mounting, intromissions, and ejaculations were the same in XY and XX males. The implications of these findings for the effect of sex chromosome complement on sex differences in aggression and mating in mice are discussed.
对C57BL/6/J/Ei（“C57BL/6”或“B6”）品系小鼠的XX雌性、XY雌性和XY雄性的攻击行为和交配行为进行了评估。XY雌性的Y染色体来源于波氏小家鼠（Mus domesticus poschiavinus），XY雄性的Y染色体来源于小家鼠（Mus musculus）。C57BL/6背景下的波氏小家鼠Y染色体导致XY小鼠具有卵巢或卵睾。仅对有卵巢的小鼠进行了测试。这些XY雌性在内分泌方面似乎与XX雌性相同。还对FVB/NtacfBR Odsex（“FVB”）品系小鼠的XX雄性和XY雄性的攻击行为和交配行为进行了测试。XX雄性在SOX9基因上游1 Mb处插入了一个转基因，导致在没有Y染色体的情况下性腺分化为睾丸。对C57BL/6小鼠在煽动性的驻留入侵者范式中进行攻击行为测试，对FVB/NtacfBR Odsex小鼠在中性笼范式中进行攻击行为测试。两个品系的小鼠都与具有相同性染色体组成和性腺性别的对手进行测试。在C57BL/6背景下，XY雄性比XY和XX雌性更具攻击性，但XX和XY雌性在攻击性方面没有显著差异。在FVB背景下，XY和XX雄性的攻击性相同。对来自C57BL/6和FVB背景的小鼠与处于激素发情期的雌性进行交配行为测试。在C57BL/6背景下，XY雄性的骑跨行为多于XY雌性，但XY和XX雌性在骑跨行为方面没有显著差异。在FVB背景下，XY和XX雄性的骑跨、插入和射精行为相同。讨论了这些发现对性染色体组成对小鼠攻击和交配性别差异影响的意义。
