Comparisons On 10-HDA Content And Proteomics Of Madibular Gland Of Worker Honey Bees At Different Ages(Apis Cerana Cerana)

Mandibular gland is very important for honey bee worker,which secrets 10-hydroxy-2-decenoic acid(10-HDA),a major unsaturated fatty acid component,to royal jelly.10-HDA plays an important role in royal jelly preservation as well as in caste determination in female larvae development.Chinese honeybee(Apis cerana cerana)is a major native species in China,which has many unique properties different to European honey bee.In order to explore the synthesis and secretion of 10-HDA in mandibular gland of A.cerana cerana worker,we compared the proteins in mandibular glands of different aged worker honey bees by using proteomics methods.At first,10-HDA in the heads of workers at 0,5,10,15,20,25,30,35,40,45,50,55 days old were measured by HPLC.The results showed that,the amount of 10-HDA is quite low in newly emerged(0-day old)workers,the average was 0.43±0.24 ?g/bee.it significantly increased(P<0.01),and up to 5.56±0.71 ?g/bee(P<0.05)at 10-day old,it decreased slightly at 15-day old worker,however no significant difference was found(P>0.05).It decreased significantly afterwards(P<0.05),to the similar level after 25 days later(P>0.05).Secondly,the proteins of mandibular gland of 0,10,15,20,25,30 days old workers were extracted and run in two-dimensional electrophoresis(2DE)gels,then those differential protein spots were picked up for mass spectrum analysis.About 18 differential proteins were found,which function in cell structure,receptors,cell communication,stress proteins,mitochondrion,and energy production proteins.Furthermore,Isobaric tags for relative and absolute quantitation(iTRAQ)was used for proteins comparison of madibular glands of 0-day old and 10-day old workers.829 proteins were detected in total,and 182 proteins were found significantly expressed,of which 89 proteins were up-regulated and 93 proteins were down-regulated.Fatty acid synthase in 10-day old worker's mandibular gland was significantly higher expressed than in newly emerged worker.These will pave the way for future elucidating the functions of these differential proteins and the synthesis pathway of 10-HDA.