1
|
Racca AC, Ridano ME, Bandeira CL, Bevilacqua E, Avvad Portari E, Genti-Raimondi S, Graham CH, Panzetta-Dutari GM. Low oxygen tension induces Krüppel-Like Factor 6 expression in trophoblast cells. Placenta 2016; 45:50-7. [PMID: 27577710 DOI: 10.1016/j.placenta.2016.07.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Revised: 07/06/2016] [Accepted: 07/25/2016] [Indexed: 12/11/2022]
Abstract
The transcription factor Krüppel-Like Factor 6 (KLF6) has important roles in cell differentiation, angiogenesis, apoptosis, and proliferation. Furthermore, there is evidence that KLF6 is required for proper placental development. While oxygen is a critical mediator of trophoblast differentiation and function, the involvement of oxygen in the regulation of KLF6 expression remains unexplored. In the present study we examined the expression of KLF6 in placental tissue from uncomplicated and preeclamptic pregnancies, the latter often characterized by an inadequately perfused placenta. We also determined the effect of hypoxia and the involvement of Hypoxia-Inducible Factor 1α (HIF-1α) on the expression of KLF6 in cultured trophoblast cells and placental tissues. Results revealed that villous, interstitial and endovascular extravillous cytotrophoblasts from placentas from normal and preeclamptic pregnancies express KLF6. In addition, KLF6 immunoreactivity was higher in the placental bed of preeclamptic pregnancies than in those of uncomplicated pregnancies. We demonstrated that hypoxia induced an early and transient increase in KLF6 protein levels in HTR8/SVneo extravillous cytotrophoblast cells and in placental explants. Reoxygenation returned KLF6 protein to basal levels. Moreover, hypoxia-induced up-regulation of KLF6 expression was dependent on HIF-1α as revealed by siRNA knockdown in HTR8/SVneo cells. These results indicate that KLF6 may mediate some of the effects of hypoxia in placental development. The regulation of KLF6 protein levels by oxygen has significant implications for understanding its putative role in diseases affected by tissue hypoxia.
Collapse
Affiliation(s)
- A C Racca
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - M E Ridano
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - C L Bandeira
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | - E Bevilacqua
- Department of Cell and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, Brazil
| | - E Avvad Portari
- Department of Pathology at Medical Sciences School, State University of Rio de Janeiro, Brazil
| | - S Genti-Raimondi
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina
| | - C H Graham
- Departments of Biomedical and Molecular Sciences and Urology, Queen's University, Kingston, Ontario, Canada
| | - G M Panzetta-Dutari
- Centro de Investigaciones en Bioquímica Clínica e Inmunología (CIBICI-CONICET), Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, Argentina.
| |
Collapse
|
2
|
Nores R, Blanchon L, López-Díaz F, Bocco JL, Patrito LC, Sapin V, Panzetta-Dutari GM. Transcriptional control of the human pregnancy-specific glycoprotein 5 gene is dependent on two GT-boxes recognized by the ubiquitous specificity protein 1 (Sp1) transcription factor. Placenta 2004; 25:9-19. [PMID: 15013634 DOI: 10.1016/s0143-4004(03)00213-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2003] [Revised: 07/03/2003] [Accepted: 07/29/2003] [Indexed: 11/28/2022]
Abstract
Pregnancy-specific glycoprotein 5 gene (PSG-5) belongs to the human pregnancy-specific glycoprotein family, encoded by eleven highly similar and transcriptionally active genes. High levels of PSG biosynthesis are restricted to the placenta syncytiotrophoblast and are essential for the maintenance of normal gestation in mammalian species. We have investigated here the nature of the transcription factors that recognize the FP1 (-455/-433) and the CPE (-147/-140) regulatory sequences that significantly contribute to basal PSG-5 promoter activity. Both elements bear a similar GT-box motif; and DNA-protein complex formation, as well as promoter activity, is largely dependent on the integrity of these GT-box sequences. Gel shift, super gel shift and UV-crosslinking experiments clearly demonstrate that the ubiquitous specificity protein 1 (Sp1) is the major transcription factor involved in complex formation with both cis-acting elements in normal term placenta tissue and in PSG-non-expressing COS-7 cells. Furthermore, transfection experiments indicate that Sp1 activates PSG-5 promoter constructs. In addition, we show that Sp1 is indeed co-expressed with PSG genes in the syncytiotrophoblast cells, stressing its potential role in the in vivo regulation of PSG expression.
Collapse
Affiliation(s)
- R Nores
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Haya de la Torre, Ciudad Universitaria, 5000 Córdoba, Argentina
| | | | | | | | | | | | | |
Collapse
|
3
|
Demarchi DA, Panzetta-Dutari GM, Colantonio SE, Marcellino AJ. Absence of the 9-bp deletion of mitochondrial DNA in pre-Hispanic inhabitants of Argentina. Hum Biol 2001; 73:575-82. [PMID: 11512683 DOI: 10.1353/hub.2001.0050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
We investigated the incidence of the Region V mitochondrial DNA 9-base-pair (bp) deletion from human remains recovered from several archaeological sites and contexts throughout Argentina. Of the 34 samples analyzed, 24 yielded DNA extractions that gave clear amplification results. All of the individuals carried two repeats of the 9 bp, one of which has been shown to be deleted in some individuals of Asian origin and defines mitochondrial lineage B. Although most of the modern Amerindian groups in the region exhibit the deletion in high frequencies, the absence of the 9-bp deletion among ancient populations of South America seems to be the rule rather than the exception, as was reported by several studies involving extinct populations. The evidence gathered until now suggests that the earliest settlers of this region of South America did not carry mitochondrial lineage B.
Collapse
Affiliation(s)
- D A Demarchi
- Cátedra de Antropología Biológica y Cultural, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Argentina
| | | | | | | |
Collapse
|
4
|
Demarchi DA, Panzetta-Dutari GM, Motran CC, López de Basualdo MA, Marcellino AJ. Mitochondrial DNA haplogroups in Amerindian populations from the Gran Chaco. Am J Phys Anthropol 2001; 115:199-203. [PMID: 11424071 DOI: 10.1002/ajpa.1074] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Mitochondrial DNA from 141 individuals was typed for diagnostic restriction sites and the 9-bp region V deletion to examine the distribution of the founding mtDNA lineage haplotypes in three Amerindian populations (Mataco, Toba, and Pilagá) who currently inhabit the Argentinian part of the Gran Chaco. All four lineages were identified in the three tribes and four population samples studied. Disregarding ethnic or geographic origin, haplogroups B and D exhibit high incidence among the Gran Chaco inhabitants, whereas haplogroups A and C are present in a lower frequency. Three individuals possess none of the characteristic markers and, therefore, could not be assigned to one of those lineages. A neighbor-joining representation of F(ST) distances reflects the current geographic location of the populations, and this also corresponds to their historic distribution. After separating South America into four major regions (Tropical Forest, Andes, Gran Chaco, and Patagonia-Tierra del Fuego), the Gran Chaco populations present the highest average intragroup variability (Hs = 0.64) as well as the lowest intergroup diversity (G(')(ST) = 0.06). These findings suggest high levels of gene flow among the Chaco tribes, as well as with neighbor populations from outside the region.
Collapse
Affiliation(s)
- D A Demarchi
- Cátedra de Antropología Biológica y Cultural, Facultad de Ciencias Exactas, Físicas y Naturales, Universidad Nacional de Córdoba, Av. Vélez Sársfield 299, 5000 Córdoba, Argentina.
| | | | | | | | | |
Collapse
|
5
|
Panzetta-Dutari GM, Koritschoner NP, Bocco JL, Nores R, Dumur CI, Patrito LC. Transcription of genes encoding pregnancy-specific glycoproteins is regulated by negative promoter-selective elements. Biochem J 2000; 350 Pt 2:511-9. [PMID: 10947966 PMCID: PMC1221279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The human pregnancy-specific glycoprotein (PSG) genes comprise a family of 11 highly conserved members whose expression is maximal in placental cells and marginal in other cell types. We have investigated here the molecular basis of PSG regulation by analysing a large regulatory region of the PSG-5 gene in cells that do and do not express these genes. The promoter region (-254 to -43), which does not contain a TATA-box, large GC-rich sequences or a classical initiator, was active in all cell types analysed. Additional upstream sequences up to position -3204 repressed promoter activity. Two independent repressor regions were identified and found to operate effectively in HeLa, COS-7 and HTR8/SVneo placental cells. More significantly, these negatively acting modules failed to repress a heterologous TATA-containing thymidine kinase promoter. Detailed transcriptional and DNA-protein analyses of the proximal repressor region (-605 to -254) revealed the presence of both negative and positive cis-acting elements. Disruption of the repressive functions resulted in an enhanced transcription of the reporter constructs. In conclusion, these results demonstrate that PSG-5 gene transcription is highly repressed by promoter-selective negative regulatory regions and the relief of repression allows enhanced PSG-5 gene transcription irrespective of the cell type. Furthermore, our findings suggest that PSG genes are expressed mainly through a derepression mechanism.
Collapse
Affiliation(s)
- G M Panzetta-Dutari
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ala Oeste, Ciudad Universitaria, 5000 Cordoba, Argentina
| | | | | | | | | | | |
Collapse
|
6
|
Rondan Dueñas JC, Panzetta-Dutari GM, Gardenal CN. Specific requirements for PCR amplification of long mitochondrial A+T-rich DNA. Biotechniques 1999; 27:258-60. [PMID: 10457825 DOI: 10.2144/99272bm08] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
|
7
|
Koritschoner NP, Bocco JL, Panzetta-Dutari GM, Dumur CI, Flury A, Patrito LC. A novel human zinc finger protein that interacts with the core promoter element of a TATA box-less gene. J Biol Chem 1997; 272:9573-80. [PMID: 9083102 DOI: 10.1074/jbc.272.14.9573] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
We describe a novel human cDNA isolated by target site screening of a placental expression library, using as a probe, an essential element of a TATA box-less promoter corresponding to a pregnancy-specific glycoprotein gene. The cDNA encoded a predicted protein of 290 amino acids, designated core promoter-binding protein (CPBP), which has three zinc fingers (type Cys2-His2) at the end of its C-terminal domain, a serine/threonine-rich central region and an acidic domain lying within the N-terminal region. Additional sequence analysis and data base searches revealed that only the zinc finger domains are conserved (60-80% identity) in other transcription factors. In cotransfection assays, CPBP increased the transcription from a minimal promoter containing its natural DNA-binding site. Moreover, a chimeric protein between CPBP and Gal4 DNA binding domain also increased the activity of an heterologous reporter gene containing Gal4 DNA binding sites. The tissue distribution analysis of CPBP mRNA revealed that it is differentially expressed with an apparent enrichment in placental cells. The DNA binding and transcriptional activity of CPBP, in conjunction with its expression pattern, strongly suggests that this protein may participate in the regulation and/or maintenance of the basal expression of PSG and possibly other TATA box-less genes.
Collapse
Affiliation(s)
- N P Koritschoner
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Cordoba, Argentina
| | | | | | | | | | | |
Collapse
|
8
|
Koritschoner NP, Panzetta-Dutari GM, Bocco JL, Dumur CI, Flury A, Patrito LC. Analyses of cis-acting and trans-acting elements that are crucial to sustain pregnancy-specific glycoprotein gene expression in different cell types. Eur J Biochem 1996; 236:365-72. [PMID: 8612604 DOI: 10.1111/j.1432-1033.1996.00365.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Pregnancy-specific beta 1 glycoprotein genes (PSG) are mainly expressed during human placental development, though their expression has been reported in other normal and pathological tissues, e.g. hydatidiform mole (HM), of distinct origins. However, the molecular components implicated in the regulation of PSG are not well understood. To identify some of the regulatory elements involved in the transcriptional control of PSG expression, the DNA-protein interactions and the basal activities of the TATA-box-less PSG5 promoter were determined in different tissues and cell types. In DNAse-I protection assays, DNA-binding proteins from human term placenta (HTP) protected a region of 27 bp located from nucleotides --150 to --124, overlapping the farthest 5' upstream cap site and resembling an initiator-like element. In electrophoretic mobility shift assays (EMSA), three complexes were detected using nuclear extracts from HTP and an oligonucleotide containing the 27-bp motif. In situ ultraviolet crosslinking analysis of the specific complexes revealed that two proteins of 78.0 kDa and 53.0 kDa are involved in such interactions, in accordance with the bands of 80.0 kDa and 57.5 kDa observed by Southwestern blotting. Competitive EMSA using mutant oligonucleotides with the substitution of 5'ACCCAT3' by 5'GATATC3' within the 27-bp motif revealed that this sequence is fundamental for the formation of the specific DNA-protein complexes. We show in transient transfection experiments performed in HeLa, COS-7 and JEG-3 cells, that such mutation completely abolished the transcriptional activity of the PSG5 promoter, independently of the cell type. Moreover, this mutation disrupted the formation of the specific DNA-protein complexes which were essentially the same as those displayed by HTP. We also determined the binding activities of nucleoproteins derived from placental tissues in earlier developmental and pathological stages, i.e. first trimester placenta (1-TRIM) and HM, respectively, showing that the DNA-binding patterns were different from each other and distinct from those elicited by HTP. Our results indicate that the cis-acting and trans-acting elements analyzed are indispensable to support PSG5 promoter activity in cell lines which do or do not produce PSG. In addition, these elements appear to play a role in the mechanisms involved in PSG basal expression during placental development and differentiation.
Collapse
Affiliation(s)
- N P Koritschoner
- Departamento de Bioquímica Clínica, Facultad de Ciencias Quimicas, Universidad Nacional de Córdoba, Argentina
| | | | | | | | | | | |
Collapse
|
9
|
Panzetta-Dutari GM, Bocco JL, Reimund B, Flury A, Patrito LC. Nucleotide sequence of a pregnancy-specific beta 1 glycoprotein gene family member. Identification of a functional promoter region and several putative regulatory sequences. Mol Biol Rep 1992; 16:255-62. [PMID: 1454058 DOI: 10.1007/bf00419665] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
The pregnancy-specific beta 1 glycoprotein (PSG) genes encode a group of heterogeneous proteins produced in large amounts by the human syncytiotrophoblast. Their expression seems to be regulated at the transcriptional level during normal pregnancy. In the present work, we isolated from a human placental library a 17 kb genomic fragment corresponding to a member of the PSG multigene family. DNA sequence analysis of 1190 nucleotides upstream of the translational start and of the first intron, revealed the presence of several putative regulatory sequences. In a transient chloramphenicol acetyltransferase expression assay, 5' flanking sequences within 123 nucleotides upstream to the first major transcription initiation site, functioned as a strong promoter in COS-7 cells. Meanwhile, sequences 5' further upstream had the ability to abolish this promoter activity. The sequence analyzed did not contain any obvious TATA-like boxes or G+C-rich regions, suggesting the existence of unique promoter elements implicated in transcription initiation and regulation of this PSG gene family member.
Collapse
Affiliation(s)
- G M Panzetta-Dutari
- Departamento de Bioquímica Clínica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Argentina
| | | | | | | | | |
Collapse
|