title: Expression of PLIN2 and PLIN3 during oocyte maturation and early embryo development in cattle.
abstract: In vitro-produced embryos store high lipid content in cytoplasmic lipid droplets (LD), and reduction or removal of LD has been demonstrated to improve freeze-thaw viability. The Perilipin Adipophilin Tail-interacting Protein of 47 kD (PAT) family of proteins is involved in the formation and regulation of LD in many cell types, but their presence has not been addressed either in cattle oocytes or preimplantation embryos. Therefore, this study aimed to detect the expression of PAT family transcripts (Perilipin-2 [PLIN2] and Perilipin-3 [PLIN3]) in immature and in vitro-matured (IVM) oocytes, and in in vitro-produced embryos at the stages of two to four cells, eight to 16 cells, morulae (MO), and blastocyst (BL). The expression of PLIN3 was downregulated in response to IVM, and PLIN2 was comparatively more expressed than PLIN3 in IVM oocytes (P < 0.001). During the early stages of embryo development, PLIN2 expression reached its peak at the MO stage (P < 0.001) and decreased again at the BL stage. In contrast, PLIN3 was expressed in low levels during the earliest stages of development, slightly upregulated at the MO stage (P < 0.05), and greatly increased its expression at the BL stage (15-fold; P < 0.001). PLIN3 was comparatively more expressed than PLIN2 during embryo culture in most stages analyzed (P < 0.05), except in eight- to 16-cell embryos. These results indicate that PLIN2 might be involved in the maintenance of lipid stocks necessary to support embryo development after fertilization of IVM oocytes. Also, we hypothesize that PLIN3 is the main PAT protein responsible for stabilization of LD formed in consequence of the acute lipid load seen during embryo development. We confirmed the presence of both PLIN2 and PLIN3 proteins in BL at Day 7 using immunocytochemistry: these PAT proteins colocalized with LD stained with BODIPY. PLIN3 seemed to be more ubiquitously spread out in the cytoplasm than PLIN2, consistent with the pattern seen in adipocytes. These findings suggest that both elderly (bigger) and newly formed (smaller) LD, positive for PLIN2 and PLIN3 respectively, coexist in blastocysts. To our knowledge this is the first report showing that transcripts of the PAT family are present in cattle oocytes and embryos.
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Danuta
authors.initials: D
authors.lastname: Sastre
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Nathália Nogueira
authors.initials: NN
authors.lastname: da Costa
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: André Luiz Alves
authors.initials: AL
authors.lastname: de Sá
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Stefanne Dhúllia Braga
authors.initials: SD
authors.lastname: Conceição
authors.affiliation: Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Pirassununga, São Paulo, Brasil.
authors.forename: Marcos Roberto
authors.initials: MR
authors.lastname: Chiaratti
authors.affiliation: Universidade Norte do Paraná, Paraná, Brasil; Agropecuária Laffranchi, Tamarana, Paraná, Brasil.
authors.forename: Paulo Roberto
authors.initials: PR
authors.lastname: Adona
authors.affiliation: Universidade Norte do Paraná, Paraná, Brasil; Agropecuária Laffranchi, Tamarana, Paraná, Brasil.
authors.forename: Samuel
authors.initials: S
authors.lastname: Guemra
authors.affiliation: Faculdade de Zootecnia e Engenharia de Alimentos, Universidade de São Paulo, Pirassununga, São Paulo, Brasil.
authors.forename: Flávio Vieira
authors.initials: FV
authors.lastname: Meirelles
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Simone do Socorro Damasceno
authors.initials: Sdo S
authors.lastname: Santos
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Sena
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Otávio Mitio
authors.initials: OM
authors.lastname: Ohashi
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil.
authors.forename: Eduardo José Melo
authors.initials: EJ
authors.lastname: dos Santos
authors.affiliation: Instituto de Ciências Biológicas, Universidade Federal do Pará, Belém, Pará, Brasil. Electronic address: moyses_m@yahoo.com.
authors.forename: Moysés dos Santos
authors.initials: Mdos S
authors.lastname: Miranda
mesh_terms: D000818:Animals; D002417:Cattle / Q000196:embryology*; D047108:Embryonic Development; D005307:Fertilization in Vitro / Q000662:veterinary; D008565:Membrane Proteins / Q000378:metabolism*; D009865:Oocytes / Q000254:growth & development*; D000070780:Perilipin-2; D033921:Vesicular Transport Proteins / Q000378:metabolism*
chemical_list: D008565:Membrane Proteins; D000070780:Perilipin-2; D033921:Vesicular Transport Proteins
keywords: ADRP; Bovine; Embryo; Oocyte; Perilipin; TIP47