title: PROTEINS OF THE INTEGUMENTARY SYSTEM OF THE HONEYBEE, Apis mellifera.
abstract: The integument of insects and other arthropods is composed of an inner basal lamina coated by the epidermis, which secretes the bulk of the outer integument layer, the cuticle. The genome sequencing of several insect species has allowed predicting classes of proteins integrating the cuticle. However, only a small proportion of them, as well as other proteins in the integumentary system, have been validated. Using two-dimensional gel electrophoresis coupled with mass spectrometry, we identified 45 different proteins in a total of 112 selected gel spots derived from thoracic integument samples of developing honeybee workers, including 14 cuticular proteins (AmelCPR 3, AmelCPR 12, AmelCPR 16, AmelCPR 27, apidermin 2, apidermin 3, endocuticle structural glycoprotein SgAbd-8-like, LOC100577363, LOC408365, LOC413679, LOC725454, LOC100576916, LOC725838, and peritrophin 3-C analogous). Gene ontology functional analysis revealed that the higher proportions of the identified proteins have molecular functions related to catalytic and structural molecule activities, are involved in metabolic biological processes, and pertain to the protein class of structural or cytoskeletal proteins and hydrolases. It is noteworthy that 26.7% of the identified proteins, including five cuticular proteins, were revealed as protein species resulting from allelic isoforms or derived from posttranslational modifications. Also, 66.7% of the identified cuticular proteins were expressed in more than one developmental phase, thus indicating that they are part of the larval, pupal, and adult cuticle. Our data provide experimental support for predicted honeybee gene products and new information on proteins expressed in the developing integument.
authors.affiliation: Departamento de Genética, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: André Fernando Ditondo
authors.initials: AF
authors.lastname: Micas
authors.affiliation: Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Centro de Química de Proteínas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Germano Aguiar
authors.initials: GA
authors.lastname: Ferreira
authors.affiliation: Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Centro de Química de Proteínas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Helen Julie
authors.initials: HJ
authors.lastname: Laure
authors.affiliation: Departamento de Biologia Celular e Molecular e Bioagentes Patogênicos, Centro de Química de Proteínas, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: José Cesar
authors.initials: JC
authors.lastname: Rosa
authors.affiliation: Departamento de Biologia, Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil.
authors.forename: Márcia Maria Gentile
authors.initials: MM
authors.lastname: Bitondi
mesh_terms: D000818:Animals; D001516:Bees / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D015870:Gene Expression; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D034582:Integumentary System / Q000502:physiology; D007814:Larva / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D011679:Pupa / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D019476:Insect Proteins
keywords: Apis mellifera; cuticular proteins; epidermis; exoskeleton; integument