1
|
Melatonin Alleviates Oxidative Stress Induced by H2O2 in Porcine Trophectodern Cells. Antioxidants (Basel) 2022; 11:antiox11061047. [PMID: 35739944 PMCID: PMC9219737 DOI: 10.3390/antiox11061047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 05/13/2022] [Accepted: 05/18/2022] [Indexed: 01/17/2023] Open
Abstract
Placental oxidative stress has been implicated as a main risk factor for placental dysfunction. Alleviation of oxidative stress and enhancement of antioxidant capacity of porcine trophectoderm (PTr2) cells are effective means to maintaining normal placental function. The present study was conducted to evaluate the protective effect of melatonin (MT) on H2O2-induced oxidative damage in PTr2 cells. Our data revealed that pretreatment with MT could significantly improve the decrease in cell viability induced by H2O2, and reduce intracellular reactive oxygen species (ROS) levels and the ratio of apoptotic cells. Here, we compared the transcriptomes of untreated versus melatonin-treated PTr2 cells by RNA-seq analysis and found that differentially expressed genes (DEGs) were highly enriched in the Wnt signaling, TGF-beta signaling and mTOR signaling pathways. Moreover, pretreatment with MT upregulated the antioxidant-related genes such as early growth response3 (EGR3), WAP four-disulfide core domain1 (WFDC1), heme oxygenase1 (HMOX1) and vimentin (VIM). These findings reveal that melatonin protects PTr2 cells from H2O2-induced oxidative stress damage.
Collapse
|
2
|
Thapa M, Johnson E, Rance M. Effect of monovalent ion binding on molecular dynamics of the S100-family calcium-binding protein calbindin D 9k. J Comput Chem 2019; 40:1936-1945. [PMID: 30977915 DOI: 10.1002/jcc.25839] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 02/25/2019] [Accepted: 03/23/2019] [Indexed: 11/06/2022]
Abstract
Calbindin D9k is a member of the S100 subfamily of EF-hand calcium binding proteins, and has served as an important model system for biophysical studies. The fast timescale dynamics of the calcium-free (apo) state is characterized using molecular dynamics simulations. Order parameters for the backbone NH bond vectors are determined from the simulations and compared with experimentally derived values, with a focus on the dynamics of calcium-binding site I. There is a significant discrepancy between simulated and experimental order parameters for site I residues in the case of no ion bound in site I. However, it was found in the simulations that a Na+ ion can bind in site I, and the resulting order parameters determined from the simulations are in excellent agreement with experiment. Comparisons are made to X-ray structures of other S100 family members in which Na+ ions were observed or suggested to be bound in site I. © 2019 Wiley Periodicals, Inc.
Collapse
Affiliation(s)
- Mahendra Thapa
- Department of Physics, University of Cincinnati, Cincinnati, Ohio
| | - Eric Johnson
- Department of Chemistry and Physical Sciences, Mount St. Joseph University, Cincinnati, Ohio
| | - Mark Rance
- Department of Molecular Genetics, Biochemistry and Microbiology, University of Cincinnati College of Medicine, Cincinnati, Ohio
| |
Collapse
|
3
|
Baird-Titus JM, Thapa M, Doerdelmann T, Combs KA, Rance M. Lysine Side-Chain Dynamics in the Binding Site of Homeodomain/DNA Complexes As Observed by NMR Relaxation Experiments and Molecular Dynamics Simulations. Biochemistry 2018; 57:2796-2813. [PMID: 29664630 DOI: 10.1021/acs.biochem.8b00195] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An important but poorly characterized contribution to the thermodynamics of protein-DNA interactions is the loss of entropy that occurs from restricting the conformational freedom of amino acid side chains. The effect of restricting the flexibility of several side chains at a protein-DNA interface may be comparable in many cases to the other factors that determine the binding thermodynamics and may, therefore, play a key role in dictating the binding affinity and/or specificity. Because the entropic contributions, including the presence and influence of side-chain dynamics, are especially difficult to estimate based on structural information, it is important to pursue experimental and theoretical studies that can provide direct information regarding these issues. We report on studies of a model system, the homeodomain/DNA complex, focusing on the Lys50 class of homeodomains where a key lysine residue in position 50 was shown previously to be critical for binding site specificity. NMR methodology was employed for determining the dynamics of lysine side-chain amino groups via 15N relaxation measurements in the Lys50-class homeodomains from the Drosophila protein Bicoid and the human protein Pitx2. In the case of Pitx2, complexes with both a consensus and a nonconsensus DNA binding site were examined. NMR-derived order parameters indicated moderate to substantial conformational freedom for the lysine NH3+ group in the complexes studied. To complement the experimental NMR measurements, molecular dynamics simulations were performed for the consensus complexes to gain further, detailed insights regarding the dynamics of the Lys50 side chain and other important residues in the protein-DNA interface.
Collapse
Affiliation(s)
- Jamie M Baird-Titus
- Department of Chemistry and Physical Sciences , Mount St. Joseph University , Cincinnati , Ohio 45233 , United States
| | - Mahendra Thapa
- Department of Physics , University of Cincinnati , Cincinnati , Ohio 45220 , United States
| | - Thomas Doerdelmann
- Department of Molecular Genetics, Biochemistry and Microbiology , University of Cincinnati College of Medicine , Cincinnati , Ohio 45267 , United States
| | - Kelly A Combs
- Department of Molecular Genetics, Biochemistry and Microbiology , University of Cincinnati College of Medicine , Cincinnati , Ohio 45267 , United States
| | - Mark Rance
- Department of Molecular Genetics, Biochemistry and Microbiology , University of Cincinnati College of Medicine , Cincinnati , Ohio 45267 , United States
| |
Collapse
|
4
|
Hendee KE, Sorokina EA, Muheisen SS, Reis LM, Tyler RC, Markovic V, Cuturilo G, Link BA, Semina EV. PITX2 deficiency and associated human disease: insights from the zebrafish model. Hum Mol Genet 2018; 27:1675-1695. [PMID: 29506241 PMCID: PMC5932568 DOI: 10.1093/hmg/ddy074] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Revised: 01/30/2018] [Accepted: 02/26/2018] [Indexed: 02/06/2023] Open
Abstract
The PITX2 (paired-like homeodomain 2) gene encodes a bicoid-like homeodomain transcription factor linked with several human disorders. The main associated congenital phenotype is Axenfeld-Rieger syndrome, type 1, an autosomal dominant condition characterized by variable defects in the anterior segment of the eye, an increased risk of glaucoma, craniofacial dysmorphism and dental and umbilical anomalies; in addition to this, one report implicated PITX2 in ring dermoid of the cornea and a few others described cardiac phenotypes. We report three novel PITX2 mutations-c.271C > T, p.(Arg91Trp); c.259T > C, p.(Phe87Leu); and c.356delA, p.(Gln119Argfs*36)-identified in independent families with typical Axenfeld-Rieger syndrome characteristics and some unusual features such as corneal guttata, Wolf-Parkinson-White syndrome, and hyperextensibility. To gain further insight into the diverse roles of PITX2/pitx2 in vertebrate development, we generated various genetic lesions in the pitx2 gene via TALEN-mediated genome editing. Affected homozygous zebrafish demonstrated congenital defects consistent with the range of PITX2-associated human phenotypes: abnormal development of the cornea, iris and iridocorneal angle; corneal dermoids; and craniofacial dysmorphism. In addition, via comparison of pitx2M64* and wild-type embryonic ocular transcriptomes we defined molecular changes associated with pitx2 deficiency, thereby implicating processes potentially underlying disease pathology. This analysis identified numerous affected factors including several members of the Wnt pathway and collagen types I and V gene families. These data further support the link between PITX2 and the WNT pathway and suggest a new role in regulation of collagen gene expression during development.
Collapse
Affiliation(s)
- Kathryn E Hendee
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena A Sorokina
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Sanaa S Muheisen
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Linda M Reis
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Rebecca C Tyler
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
| | - Vujica Markovic
- Faculty of Medicine, University of Belgrade, Serbia
- Clinical Centre of Serbia, University Eye Hospital, Belgrade, Serbia
| | - Goran Cuturilo
- Faculty of Medicine, University of Belgrade, Serbia
- Department of Medical Genetics, University Children’s Hospital, Belgrade, Serbia
| | - Brian A Link
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| | - Elena V Semina
- Department of Pediatrics and Children’s Research Institute Medical College of Wisconsin and Children's Hospital of Wisconsin, Milwaukee, WI 53226, USA
- Department of Cell Biology, Neurobiology, and Anatomy, Medical College of Wisconsin, Milwaukee, WI 53226, USA
- Department of Ophthalmology, Medical College of Wisconsin, Milwaukee, WI 53226, USA
| |
Collapse
|
5
|
Ji Y, Buel SM, Amack JD. Mutations in zebrafish pitx2 model congenital malformations in Axenfeld-Rieger syndrome but do not disrupt left-right placement of visceral organs. Dev Biol 2016; 416:69-81. [PMID: 27297886 DOI: 10.1016/j.ydbio.2016.06.010] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 06/05/2016] [Accepted: 06/06/2016] [Indexed: 12/18/2022]
Abstract
Pitx2 is a conserved homeodomain transcription factor that has multiple functions during embryonic development. Mutations in human PITX2 cause autosomal dominant Axenfeld-Rieger syndrome (ARS), characterized by congenital eye and tooth malformations. Pitx2(-/-) knockout mouse models recapitulate aspects of ARS, but are embryonic lethal. To date, ARS treatments remain limited to managing individual symptoms due to an incomplete understanding of PITX2 function. In addition to regulating eye and tooth development, Pitx2 is a target of a conserved Nodal (TGFβ) signaling pathway that mediates left-right (LR) asymmetry of visceral organs. Based on its highly conserved asymmetric expression domain, the Nodal-Pitx2 axis has long been considered a common denominator of LR development in vertebrate embryos. However, functions of Pitx2 during asymmetric organ morphogenesis are not well understood. To gain new insight into Pitx2 function we used genome editing to create mutations in the zebrafish pitx2 gene. Mutations in the pitx2 homeodomain caused phenotypes reminiscent of ARS, including aberrant development of the cornea and anterior chamber of the eye and reduced or absent teeth. Intriguingly, LR asymmetric looping of the heart and gut was normal in pitx2 mutants. These results suggest conserved roles for Pitx2 in eye and tooth development and indicate Pitx2 is not required for asymmetric looping of zebrafish visceral organs. This work establishes zebrafish pitx2 mutants as a new animal model for investigating mechanisms underlying congenital malformations in ARS and high-throughput drug screening for ARS therapeutics. Additionally, pitx2 mutants present a unique opportunity to identify new genes involved in vertebrate LR patterning. We show Nodal signaling-independent of Pitx2-controls asymmetric expression of the fatty acid elongase elovl6 in zebrafish, pointing to a potential novel pathway during LR organogenesis.
Collapse
Affiliation(s)
- Yongchang Ji
- Department of Cell and Developmental Biology, State University of New York, Upstate Medical University, Syracuse, NY 13210, USA
| | - Sharleen M Buel
- Department of Cell and Developmental Biology, State University of New York, Upstate Medical University, Syracuse, NY 13210, USA
| | - Jeffrey D Amack
- Department of Cell and Developmental Biology, State University of New York, Upstate Medical University, Syracuse, NY 13210, USA.
| |
Collapse
|
6
|
Yin HF, Fang XY, Jin CF, Yin JF, Li JY, Zhao SJ, Miao Q, Song FW. Identification of a novel frameshift mutation in PITX2 gene in a Chinese family with Axenfeld-Rieger syndrome. J Zhejiang Univ Sci B 2014; 15:43-50. [PMID: 24390743 PMCID: PMC3891117 DOI: 10.1631/jzus.b1300053] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2013] [Accepted: 07/01/2013] [Indexed: 11/11/2022]
Abstract
OBJECTIVE Axenfeld-Rieger syndrome (ARS) is phenotypically and genetically heterogeneous. In this study, we identified the underlying genetic defect in a Chinese family with ARS. METHODS A detailed family history and clinical data were recorded. The ocular phenotype was documented using slit-lamp photography and systemic anomalies were also documented where available. The genomic DNA was extracted from peripheral blood leukocytes. All coding exons and intron-exon junctions of paired-like homeodomain transcription factor 2 (PITX2) gene and the forkhead box C1 (FOXC1) gene were amplified by polymerase chain reaction (PCR) and screened for mutation by direct DNA sequencing. Variations detected in exon 5 of PITX2 were further evaluated with cloning sequencing. The exon 5 of PITX2 was also sequenced in 100 healthy controls, unrelated to the family, for comparison. Structural models of the wild type and mutant homeodomain of PITX2 were investigated by SWISS-MODEL. RESULTS Affected individuals exhibited variable ocular phenotypes, whereas the systemic anomalies were similar. After direct sequencing and cloning sequencing, a heterozygous deletion/insertion mutation c.198_201delinsTTTCT (p.M66Ifs*133) was revealed in exon 5 of PITX2. This mutation co-segregated with all affected individuals in the family and was not found either in unaffected family members or in 100 unrelated controls. CONCLUSIONS We detected a novel frameshift mutation p.M66Ifs*133 in PITX2 in a Chinese family with ARS. Although PITX2 mutations and polymorphisms have been reported from various ethnic groups, we report for the first time the identification of a novel deletion/insertion mutation that causes frameshift mutation in the homeodomain of PITX2 protein.
Collapse
Affiliation(s)
- Hou-fa Yin
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Xiao-yun Fang
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Chong-fei Jin
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Jin-fu Yin
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Jin-yu Li
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Su-juan Zhao
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Qi Miao
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| | - Feng-wei Song
- Eye Center, the Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou 310009, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou 310009, China
| |
Collapse
|
7
|
Bastidas M, Showalter SA. Thermodynamic and structural determinants of differential Pdx1 binding to elements from the insulin and IAPP promoters. J Mol Biol 2013; 425:3360-77. [PMID: 23796517 DOI: 10.1016/j.jmb.2013.06.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2013] [Revised: 06/11/2013] [Accepted: 06/13/2013] [Indexed: 10/26/2022]
Abstract
In adult mammals, the production of insulin and other peptide hormones, such as the islet amyloid polypeptide (IAPP), is limited to β-cells due to tissue-specific expression of a set of transcription factors, the best known of which is pancreatic duodenal homeobox protein 1 (Pdx1). Like many homeodomain transcription factors, Pdx1 binds to a core DNA recognition sequence containing the tetranucleotide 5'-TAAT-3'; its consensus recognition element is 5'-CTCTAAT(T/G)AG-3'. Currently, a complete thermodynamic profile of Pdx1 binding to near-consensus and native promoter sequences has not been established, obscuring the mechanism of target site selection by this critical transcription factor. Strikingly, while Pdx1 responsive elements in the human insulin promoter conform to the pentanucleotide 5'-CTAAT-3' sequence, the Pdx1 responsive elements in the human iapp promoter all contain a substitution to 5'-TTAAT-3'. The crystal structure of Pdx1 bound to the consensus nucleotide sequence does not explain how Pdx1 identifies this natural variation, if it does at all. Here we report a combination of isothermal calorimetric titrations, NMR spectroscopy, and extensive multi-microsecond molecular dynamics calculations of Pdx1 that define its interactions with a panel of natural promoter elements and consensus-derived sequences. Our results show a small preference of Pdx1 for a C base 5' relative to the core TAAT promoter element. Molecular mechanics calculations, corroborated by experimental NMR data, lead to a rational explanation for sequence discrimination at this position. Taken together, our results suggest a molecular mechanism for differential Pdx1 affinity to elements from the insulin and iapp promoter sequences.
Collapse
Affiliation(s)
- Monique Bastidas
- Department of Chemistry, Pennsylvania State University, 104 Chemistry Building, University Park, PA 16802, USA.
| | | |
Collapse
|