title: Influence of cloning by chromatin transfer on placental gene expression at Day 45 of pregnancy in cattle.
abstract: Poor success rates in somatic cell cloning are often attributed to abnormal early embryonic development as well as late abnormal fetal growth and placental development. Although promising results have been reported following chromatin transfer (CT), a novel cloning method that includes the remodeling of the donor nuclei in vitro prior to their transfer into enucleated oocytes, animals cloned by CT show placental abnormalities similar to those observed following conventional nuclear transfer. We hypothesized that the placental gene expression pattern from cloned fetuses was ontologically related to the frequently observed placental phenotype. The aim of the present study was to compare global gene expression by microarray analysis of Day 44-47 cattle placentas derived from CT cloned fetuses with those derived from in vitro fertilization (i.e. control), and confirm the altered mRNA and protein expression of selected molecules by qRT-PCR and immunohistochemistry, respectively. The differentially expressed genes identified in the present study are known to be involved in a range of activities associated with cell adhesion, cell cycle control, intracellular transport and proteolysis. Specifically, an imprinted gene, involved with cell proliferation and placentomegaly in humans (CDKN1C) and a peptidase that serves as a marker for non-invasive trophoblast cells in human placentas (DPP4), had mRNA and protein altered in CT placentas. It was concluded that the altered pattern of gene expression observed in CT samples may contribute to the abnormal placental development phenotypes commonly identified in cloned offspring, and that expression of imprinted as well as trophoblast invasiveness-related genes is altered in cattle cloned by CT.
authors.affiliation: Department of Animal Sciences, University of Illinois, Urbana, IL 61801, USA. fermesq@gmail.com
authors.forename: Fernando S
authors.initials: FS
authors.lastname: Mesquita
authors.forename: Sergio A
authors.initials: SA
authors.lastname: Machado
authors.forename: Jenny
authors.initials: J
authors.lastname: Drnevich
authors.forename: Pawel
authors.initials: P
authors.lastname: Borowicz
authors.forename: Zhongde
authors.initials: Z
authors.lastname: Wang
authors.forename: Romana A
authors.initials: RA
authors.lastname: Nowak
mesh_terms: D000818:Animals; D002417:Cattle; D002843:Chromatin / Q000637:transplantation*; D019976:Cloning, Organism / Q000379:methods / Q000662:veterinary*; D004624:Embryo Transfer / Q000379:methods / Q000662:veterinary; D005260:Female; D005307:Fertilization in Vitro / Q000662:veterinary; D015870:Gene Expression / Q000502:physiology*; D006801:Humans; D020411:Oligonucleotide Array Sequence Analysis / Q000662:veterinary; D010920:Placenta / Q000378:metabolism* / Q000502:physiology; D011247:Pregnancy; D060888:Real-Time Polymerase Chain Reaction / Q000662:veterinary
chemical_list: D002843:Chromatin