We recently demonstrated that the product of HERV-W env gene, a retroviral envelope protein also dubbed syncytin, is highly fusogenic membrane glycoprotein inducing formation syncytia on interaction with type D mammalian retrovirus receptor. In addition, detection Env (Env-W) expression in placental tissue sections led us to propose role for this placenta formation. To evaluate hypothesis, we analyzed involvement Env-W differentiation primary cultures human villous cytotrophoblasts...

The syncytiotrophoblast (ST) is one of the major components human placenta, as it involved in feto-maternal exchanges and secretion pregnancy-specific hormones. aim this study was to elucidate formation function ST trisomy 21 (Down's syndrome). We first used vitro model cytotrophoblast differentiation into ST. Cytotrophoblasts were isolated from 15 21-affected placentas (12–35 weeks gestation) 10 gestational age-matched control placentas. In cytotrophoblasts normal placenta fused form This...

The syncytiotrophoblast is the principal component of human placenta involved in feto-maternal exchanges and hormone secretion. arises from fusion villous cytotrophoblasts. We recently showed that functional gap junctional intercellular communication(GJIC) an important prerequisite for formation connexin 43 (Cx43) present cytotrophoblasts syncytiotrophoblast. To determine whether Cx43 directly trophoblast fusion, we used antisense strategy primary cultures spontaneously differentiate into by...

Analysis of the skeletal phenotypes caused by genetic inactivation individual Bmps, along with study their expression patterns, suggest possible functional redundancy these molecules. To investigate effect on skeleton development combined absence some Bmp genes expressed in same areas, we have intercrossed heterozygous Bmp7 mice Bmp2 +/-, Bmp4 or Bmp5 +/- animals. Bmp2/7 and Bmp5/7 double animals do not present any abnormalities. In contrast, Bmp4/7 heterozygotes develop minor defects two...

Osteocalcin gene expression is initiated perinatally and restricted to mature osteoblasts odontoblasts. Because their pattern of highly restricted, the osteocalcin genes are excellent tools study osteoblast-specific expression. To define mechanisms cell-specific in vivo, we generated transgenic mice harboring deletion mutants promoter region OG2, one mouse genes. We show here that only 647 base pairs this sufficient confer time-specific a reporter vivo. This fragment contains two copies...

High bone resorption by the osteoclast results in osteoporosis, a disease affecting 40% of women after menopause. Calcitonin, used to treat inhibits via receptors located on osteoclasts. Two alleles calcitonin receptor gene (CTR) exist: base mutation T→C third intra-cellular C-terminal domain changes proline (CCG) at position 447 leucine (CTG). We therefore studied distribution these cohort 215 post-menopausal Caucasian suffering or not from osteoporotic fractures. The region interest within...

Trophoblastic cell-cell fusion is an essential event required during human placental development. Several membrane proteins have been described to be directly involved in this process, including connexin 43 (Cx43), syncytin 1 (Herv-W env), and 2 (Herv-FRD env glycoprotein). Recently, zona occludens (ZO) (peripheral associated with tight junctions, adherens gap junctions) were shown mouse Moreover, (ZO-1) was localized mainly at the intercellular boundaries between trophoblastic cells....

The syncytiotrophoblast (ST) is one of the major components human placenta as it involved in feto-maternal exchanges and secretion pregnancy-specific hormones.The aim this study was to elucidate formation function ST trisomy 21 (Down syndrome).We first used vitro model cytotrophoblast differentiation into ST.Cytotrophoblasts were isolated from 15 21-affected placentas (12-35 weeks gestation) 10 gestational age-matched control placentas.In cytotrophoblasts normal fused form ST.This associated...

The human insulin-family genes regulate cell growth, metabolism, and tissue-specific functions. Among these different members, only INSL4 gene shows a predominant placenta-specific expression. Here, we show that the is tightly clustered with three other members of insulin superfamily (RLN1, RLN2, INSL6) within 176-kilobase genomic segment on chromosome region 9p23.3-p24.1. We also report evidence probably insulin-like growth factor to be primate-specific. identified an unexpected endogenous...

The syncytiotrophoblast is the major component of human placenta, involved in feto-maternal exchanges and secretion pregnancy-specific hormones. Multinucleated arises from fusion mononuclear cytotrophoblast cells. In trisomy 21-affected placentas, we recently have shown that there a defect formation decrease production Due to role oxygen free radicals trophoblast cell differentiation, investigated key antioxidant enzyme, copper/zinc superoxide dismutase, encoded by chromosome 21 vitro...

Abstract Due to the key role of human chorionic gonadotropin hormone (hCG) in placental development, aim this study was characterize trophoblastic luteinizing hormone/chorionic receptor (LH/CG‐R) and investigate its expression using vitro model cytotrophoblast differentiation into syncytiotrophoblast. We confirmed by situ immunochemistry cultured cells, that LH/CG‐R is expressed both villous cytotrophoblasts syncytiotrophoblasts. However, decreased during trophoblast fusion differentiation,...

Human endogenous retroviruses (HERVs) are globally silent in somatic cells. However, some HERVs display high transcription physiological conditions. In particular, ERVWE1, ERVFRDE1 and ERV3, three proviruses of distinct families, highly transcribed placenta produce envelope proteins associated with development. As silencing repeated elements is thought to occur mainly by DNA methylation, we compared the methylation ERVWE1 related appreciate whether HERV relies upon family, integration site,...

The placenta is a transient organ essential for fetal development. During human placental development, chorionic villi grow in coordination with large capillary network resulting from both vasculogenesis and angiogenesis. Angiogenin one of the most potent inducers neovascularisation experimental models vivo. We others have previously mapped angiogenin expression term placenta. Here, we explored involvement early studied, by situ hybridisation and/or RT-PCR tissues primary cultured...

Placental development is markedly abnormal in women bearing a fetus with trisomy 21, defective syncytiotrophoblast (ST) formation and function. The ST occurs from cytotrophoblast (CT) fusion plays an essential role by secreting human chorionic gonadotropin (hCG), which to placental development. In of chromosome 21 (T21) pregnancies, CTs do not fuse differentiate properly into STs, leading the secretion weakly bioactive hCG. this study we report for first time, marked decrease number mature...

Abstract Human trophoblast expresses two fusogenic retroviral envelope proteins, the widely studied syncytin 1, encoded by HERV-W and recently characterized 2 HERV-FRD. Here we in normal Trisomy 21-affected placenta associated with abnormal differentiation. Syncytin immunolocalization was restricted throughout pregnancy to some villous cytotrophoblastic cells (CT). During second trimester of pregnancy, immunolocalized cuboidal CT T21 placentas, whereas placentas it observed flat CT,...

<title>Abstract</title> <bold>Background:</bold> The development of functional muscles in <italic>Drosophila melanogaster</italic> relies on precise spatial and temporal transcriptional control, orchestrated by complex gene regulatory networks. Central to this regulation are cis-regulatory modules (CRMs), which integrate inputs from transcription factors fine-tune expression during myogenesis. In study, we investigate the LIM-homeodomain factor Tup (Tailup/Islet-1), a key regulator dorsal...

During pregnancy, the villous trophoblast develops from fusion of cytotrophoblastic cells (CT) into a syncytiotrophoblast (ST), supporting main physiological functions human placenta. Connexin43 (Cx43) is demonstrated in situ and vitro between CT ST. Moreover, presence gap junctional intercellular communication (GJIC) during differentiation was previously demonstrated. Because exchange molecules through junctions considered to play major role control cell tissue differentiation, we studied...

Total human chorionic gonadotropin (hCG) is high in maternal serum at 14–18 wk of trisomy 21 (T21)-affected pregnancy, despite low placental hCG synthesis. We sought an explanation for this paradox. first observed that, T21-affected pregnancies, levels peaked around 10 and then followed the same pattern throughout pregnancy as controls, albeit a higher (2.2-fold) level. After delivery, clearance was not significantly different from that controls. isolated cytotrophoblasts 29 placentas (12–25...

Placental development is markedly abnormal in trisomy 21 (T21) pregnancies. We hypothesized that paracrine cross talk between the fetal mesenchymal core and trophoblast might be involved defect of syncytiotrophoblast formation function. In a large series primary cultured human cytotrophoblasts isolated from second-trimester control (n = 44) T21 placentae 71), fusion differentiation was observed more than 90% cases. then villous cells 10) 8) confirmed their origin. Conditioned medium overcame...