日本研究人員在新一期英國《自然》雜志網(wǎng)絡(luò)版上報(bào)告說，他們發(fā)現(xiàn)蜂王漿中的一種蛋白質(zhì)是蜜蜂幼蟲變身蜂王的秘密所在。
蜂群中的工蜂和蜂王都是雌性且基因相同，但蜂王的體長約是工蜂的1.5倍，而壽命更是工蜂的約20倍。此前的研究表明，能成長為蜂王的蜜蜂幼蟲的食物是蜂王漿,，而其他幼蟲的食物只是花粉和蜂蜜。但是,，蜂王漿中的何種成分促使幼蟲變身蜂王,，一直是個(gè)謎。
日本富山縣立大學(xué)講師鐮倉昌樹分別用新鮮的蜂王漿和已經(jīng)存放了30天的蜂王漿喂養(yǎng)蜜蜂幼蟲,，結(jié)果只有食用新鮮蜂王漿的幼蟲成長為蜂王,。進(jìn)一步研究發(fā)現(xiàn)，新鮮蜂王漿中一種叫做“royalactin”的蛋白質(zhì)能促進(jìn)生長激素的分泌量,，使幼蟲出現(xiàn)體格變大,、卵巢發(fā)達(dá)等蜂王的特征。
鐮倉昌樹用這種蛋白質(zhì)喂養(yǎng)果蠅,，果蠅也同樣出現(xiàn)體長,、產(chǎn)卵數(shù)和壽命等方面的增長。這說明這一蛋白質(zhì)對(duì)生物特征的影響是跨物種的,。
一個(gè)蜂群只有一個(gè)蜂王,，隨著時(shí)間推移，蜂王生殖率下降而需要淘汰更換,。這項(xiàng)成果有助于人工大量培養(yǎng)產(chǎn)卵能力強(qiáng)的蜂王,，可望在養(yǎng)蜂業(yè)中發(fā)揮作用。（生物谷Bioon.com）
生物谷推薦原文出處：
Nature doi:10.1038/nature10093
Royalactin induces queen differentiation in honeybees
Masaki Kamakura1
The honeybee (Apis mellifera) forms two female castes: the queen and the worker. This dimorphism depends not on genetic differences, but on ingestion of royal jelly, although the mechanism through which royal jelly regulates caste differentiation has long remained unknown. Here I show that a 57-kDa protein in royal jelly, previously designated as royalactin, induces the differentiation of honeybee larvae into queens. Royalactin increased body size and ovary development and shortened developmental time in honeybees. Surprisingly, it also showed similar effects in the fruitfly (Drosophila melanogaster). Mechanistic studies revealed that royalactin activated p70 S6 kinase, which was responsible for the increase of body size, increased the activity of mitogen-activated protein kinase, which was involved in the decreased developmental time, and increased the titre of juvenile hormone, an essential hormone for ovary development. Knockdown of epidermal growth factor receptor (Egfr) expression in the fat body of honeybees and fruitflies resulted in a defect of all phenotypes induced by royalactin, showing that Egfr mediates these actions. These findings indicate that a specific factor in royal jelly, royalactin, drives queen development through an Egfr-mediated signalling pathway.
