中文摘要：

外层黄茧C基因是家蚕对体内类胡萝卜素选择性吸收的关键基因之一。以13个黄红茧系品种（包括1个限性黄茧品种）、7个绿茧系品种、1个白色茧品种为材料,采用RT-PCR方法,检测和分析C基因的2个候选基因Cameo1和Cameo2在4龄和5龄幼虫不同组织的表达差异。结果表明,丝腺对黄茧色素类胡萝卜素的吸收不依赖于Cameo1基因的表达,Cameo1基因表达没有茧色和性别特异性,其蛋白产物可能没有直接参与黄茧色素吸收,而是作为B族清道夫受体家族（SCRB）成员在家蚕免疫系统中发挥作用;虽然Cameo2基因的蛋白产物介导了中肠中的黄色茧主要色素成分叶黄素的主动运输方式,但Came-o2基因不只是在家蚕黄色茧品种中肠的特异表达基因,Cameo2基因在家蚕中肠以外的组织表达特异性与这些组织的黄茧色素积累密切关联,生殖腺可能是比中肠和丝腺更加重要的Cameo2基因表达和作用的组织。

英文摘要：

The yellow cocoon gene C is a key gene related for selective carotenoid transport for cocoon coloration of Bombyx mori.In this paper,expression differences of the two candidate genes,Cameo1 and Cameo2,were analyzed by reverse transcription-polymerase chain reaction （RT-PCR） in tissues and organs of the 4th and 5th instar larvae from 13 yellow cocoon breeds （including 1 sex-limited yellow cocoon breed）,7 green cocoon breeds and 1 white cocoon breed.The results showed that the absorption of yellow pigments was not dependent on the expression of Cameo1 in the silk gland.The expression of Cameo1 gene was neither cocoon color-specific nor sex-specific.Therefore,the protein product of Cameo1 gene may not take part in the absorption of yellow pigments directly,but play the role of scavenger receptor class B （SCRB） member which functions in the immune system of B.mori.Although it was reported that the active transportation of lutein,the primary pigment of yellow cocoon,was mediated by Cameo2 protein in midgut,Cameo2 gene was not only specifically expressed in the midgut of yellow cocoon breeds.Specific expression of Cameo2 gene in tissues other than midgut was closely related to the accumulation of yellow cocoon pigments in these tissues.Furthermore,gonad might be a more important tissue than midgut and silk gland in the expression and functioning of Cameo2 gene.