Expression Of Genes Related To 10-HDA Synthesis In Mandibular Glands Of Worker Bees (apis Mellifera Ligustica)

10-HDA(10-hydroxy-2-decenoic acid,10-HDA)secreted by worker’s mandibular glands,is an very important component of roya]jelly.There were many researches about secretions of honeybee mandibular glands,however,few on fatty acid metabolism like the synthesis of 10-HDA.Fatty acid synthase(FAS)is a key enzymes in fatty acid synthesis pathway.To better understand genes related to 10-HDA synthesis and their expression in the mandibular glands as well as regulation,We used fluorescence real-time quantitative PCR to quantify the relative expression]evel offas,hsp70,mrjp1,mrp3,andtrme9 genes in mandibular gland of worker bees.Effects of exogenous factors like juvenile hormone analogue(methoprene)and feed on fas and other genes in mandibular glands of worker bees were studied too.The results were as followings:(1)The expression level of 8 candidate genes,bala、ddcp、fas、flpP、hsp70、mrjp1、mrjp3、trme9 in mandibular glands of newly emerged(0-day-old)and 10-day-old worker bees both Apis cerana cerana and Apis mellifera ligustica.were quantified.Their expression levels were all significantly different in 10-day-old bees compared to those of newly emerged bees.However,only four genes,fas,hsp70,mrjp1,mrjp3 had significant higher expression levels in 10-day-old workers’ glands.One gene,trme9 has significant lower expression levels in 10-day-old workers’ glands.Therefore,five genes,fas,hsp709 mrjp1,mrjp3,trme9 were probably taking part in the synthesis of 10-HDA.(2)0-,5-,10-,15-,20-,and 25-day-old workers’ mandibular glands were quantified for the relative expression levels of fasy mrjp1 and mrjp3 genes respectively.The results showed that the relative expression levels of mrjp1 and mrjp3 were gradually increased as workers became older,and this trend was similar to 10-HDA.Three genes may closely related to the synthesis of 10-HDA.(3)The relative expression levels of fas were quantified in mandibular glands of 0-,5-,10-,and 15-day-old worker bees supplied with different feed(sucrose syrup + pollen,longan honey + pollen,eucalyptus honey + pollen,sucrose syrup,longan honey,eucalyptus honey).The results showed that,the fas expression level of 0-day-old bee was significant lower than those of 5-,10-,15-day-old bees.The relative expression level of fas,mrjp1,mrjp3 genes could be affected by the feed,but depend on the situation.For instanee,fas and mrjp3 were significant higher expressed in those with sucrose than feed with sucrose + pollen(P<0.05),implied that pollen would inhibit these genes expression.10-HDA quantification showed that the 10-HDA content would increase with ages,and had similar trend as 10-HDA content,feed differences did not affect the 10-HDA yield.(4)After 50 μg/bees 200 μg/bee of JHA were applied on the dorsal thorax of the newly emerged(0-day-old)workers,The relative expression levels offas in mandibular glands of 3-,5-,9-day-old workers were significantly higher than those of o-day-old worker bee(P<0.01).The relative expression levels of fas in mandibular glands of 5-day-old workers treated with 200 μg/bee JHA were significant higher than those with 50 μg/bee.The result indicated JHA could increase the activity offas under certain dose of JHA.