title: Bacterial infection activates the immune system response and dysregulates microRNA expression in honey bees.
abstract: In insects, a rapid and massive synthesis of antimicrobial peptides (AMPs) is activated through signaling pathways (Toll and Imd) to combat invading microbial pathogens. However, it is still unclear whether different types of bacteria provoke specific responses. Immune response mechanisms and the activation of specific genes were investigated by challenging Apis mellifera workers with the Gram-negative bacterium Serratia marcescens or the Gram-positive bacterium Micrococcus luteus. The immune system responded by activating most genes of the Toll and Imd pathways, particularly AMP genes. However, genes specifically regulated by M. luteus or S. marcescens were not detected, suggesting an interaction between the signaling pathways that lead to immune effectors synthesis. Despite this finding, kappaB motifs in the 5'-UTRs of selected genes suggest a pathway-specific control of AMP and transferrin-1 gene expression. Regulation by miRNAs was also investigated and revealed a number of candidates for the post-transcriptional regulation of immune genes in bees.
authors.affiliation: Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Av. Bandeirantes 3900, 14049-900 Ribeirão Preto, São Paulo, Brazil. anete.lourenco@ufvjm.edu.br
authors.forename: Anete P
authors.initials: AP
authors.lastname: Lourenço
authors.forename: Karina R
authors.initials: KR
authors.lastname: Guidugli-Lazzarini
authors.forename: Flávia C P
authors.initials: FC
authors.lastname: Freitas
authors.forename: Márcia M G
authors.initials: MM
authors.lastname: Bitondi
authors.forename: Zilá L P
authors.initials: ZL
authors.lastname: Simões
mesh_terms: D000818:Animals; D001516:Bees / Q000235:genetics / Q000276:immunology / Q000382:microbiology* / Q000502:physiology*; D005786:Gene Expression Regulation; D019476:Insect Proteins / Q000235:genetics / Q000378:metabolism; D035683:MicroRNAs / Q000378:metabolism; D016982:Micrococcus luteus / Q000502:physiology*; D016328:NF-kappa B / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D012706:Serratia marcescens / Q000502:physiology*; D015398:Signal Transduction; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014168:Transferrin / Q000235:genetics / Q000378:metabolism
chemical_list: D019476:Insect Proteins; D035683:MicroRNAs; D016328:NF-kappa B; D012333:RNA, Messenger; D014157:Transcription Factors; D014168:Transferrin