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Allen RS, Biswas SK, Seifert AW. Neural crest cells give rise to non-myogenic mesenchymal tissue in the adult murid ear pinna. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.06.552195. [PMID: 37609220 PMCID: PMC10441307 DOI: 10.1101/2023.08.06.552195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/24/2023]
Abstract
Despite being a major target of reconstructive surgery, development of the external ear pinna remains poorly studied. As a craniofacial organ highly accessible to manipulation and highly conserved among mammals, the ear pinna represents a valuable model for the study of appendage development and wound healing in the craniofacial complex. Here we provide a cellular characterization of late gestational and postnatal ear pinna development in Mus musculus and Acomys cahirinus and demonstrate that ear pinna development is largely conserved between these species. Using Wnt1-cre;ROSAmT/mG mice we find that connective tissue fibroblasts, elastic cartilage, dermal papilla cells, dermal sheath cells, vasculature, and adipocytes in the adult pinna are derived from cranial crest. In contrast, we find that skeletal muscle and hair follicles are not derived from neural crest cells. Cellular analysis using the naturally occurring short ear mouse mutant shows that elastic cartilage does not develop properly in distal pinna due to impaired chondroprogenitor proliferation. Interestingly, while chondroprogenitors develop in a mostly continuous sheet, the boundaries of cartilage loss in the short ear mutant strongly correlate with locations of vasculature-conveying foramen. Concomitant with loss of elastic cartilage we report increased numbers of adipocytes, but this seems to be a state acquired in adulthood rather than a developmental abnormality. In addition, chondrogenesis remains impaired in the adult mid-distal ear pinna of these mutants. Together these data establish a developmental basis for the study of the ear pinna with intriguing insights into the development of elastic cartilage.
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Affiliation(s)
- Robyn S. Allen
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Shishir K. Biswas
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
| | - Ashley W. Seifert
- Department of Biology, University of Kentucky, Lexington, KY 40506, USA
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2
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Transcriptional Interference Regulates the Evolutionary Development of Speech. Genes (Basel) 2022; 13:genes13071195. [PMID: 35885978 PMCID: PMC9323761 DOI: 10.3390/genes13071195] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 06/30/2022] [Accepted: 06/30/2022] [Indexed: 11/17/2022] Open
Abstract
The human capacity to speak is fundamental to our advanced intellectual, technological and social development. Yet so very little is known regarding the evolutionary genetics of speech or its relationship with the broader aspects of evolutionary development in primates. In this study, we describe a large family with evolutionary retrograde development of the larynx and wrist. The family presented with severe speech impairment and incremental retrograde elongations of the pisiform in the wrist that limited wrist rotation from 180° to 90° as in primitive primates. To our surprise, we found that a previously unknown primate-specific gene TOSPEAK had been disrupted in the family. TOSPEAK emerged de novo in an ancestor of extant primates across a 540 kb region of the genome with a pre-existing highly conserved long-range laryngeal enhancer for a neighbouring bone morphogenetic protein gene GDF6. We used transgenic mouse modelling to identify two additional GDF6 long-range enhancers within TOSPEAK that regulate GDF6 expression in the wrist. Disruption of TOSPEAK in the affected family blocked the transcription of TOSPEAK across the 3 GDF6 enhancers in association with a reduction in GDF6 expression and retrograde development of the larynx and wrist. Furthermore, we describe how TOSPEAK developed a human-specific promoter through the expansion of a penta-nucleotide direct repeat that first emerged de novo in the promoter of TOSPEAK in gibbon. This repeat subsequently expanded incrementally in higher hominids to form an overlapping series of Sp1/KLF transcription factor consensus binding sites in human that correlated with incremental increases in the promoter strength of TOSPEAK with human having the strongest promoter. Our research indicates a dual evolutionary role for the incremental increases in TOSPEAK transcriptional interference of GDF6 enhancers in the incremental evolutionary development of the wrist and larynx in hominids and the human capacity to speak and their retrogression with the reduction of TOSPEAK transcription in the affected family.
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3
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Heller IS, Guenther CA, Meireles AM, Talbot WS, Kingsley DM. Characterization of mouse Bmp5 regulatory injury element in zebrafish wound models. Bone 2022; 155:116263. [PMID: 34826632 PMCID: PMC9007314 DOI: 10.1016/j.bone.2021.116263] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 11/17/2021] [Accepted: 11/18/2021] [Indexed: 11/21/2022]
Abstract
Many key signaling molecules used to build tissues during embryonic development are re-activated at injury sites to stimulate tissue regeneration and repair. Bone morphogenetic proteins provide a classic example, but the mechanisms that lead to reactivation of BMPs following injury are still unknown. Previous studies have mapped a large "injury response element" (IRE) in the mouse Bmp5 gene that drives gene expression following bone fractures and other types of injury. Here we show that the large mouse IRE region is also activated in both zebrafish tail resection and mechanosensory hair cell injury models. Using the ability to test multiple constructs and image temporal and spatial dynamics following injury responses, we have narrowed the original size of the mouse IRE region by over 100 fold and identified a small 142 bp minimal enhancer that is rapidly induced in both mesenchymal and epithelial tissues after injury. These studies identify a small sequence that responds to evolutionarily conserved local signals in wounded tissues and suggest candidate pathways that contribute to BMP reactivation after injury.
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Affiliation(s)
- Ian S Heller
- Department of Developmental Biology, Stanford University School of Medicine, United States of America
| | - Catherine A Guenther
- Department of Developmental Biology, Stanford University School of Medicine, United States of America; Howard Hughes Medical Institute, Stanford University School of Medicine, United States of America
| | - Ana M Meireles
- Department of Developmental Biology, Stanford University School of Medicine, United States of America
| | - William S Talbot
- Department of Developmental Biology, Stanford University School of Medicine, United States of America
| | - David M Kingsley
- Department of Developmental Biology, Stanford University School of Medicine, United States of America; Howard Hughes Medical Institute, Stanford University School of Medicine, United States of America.
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4
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Castro JPL, Yancoskie MN, Marchini M, Belohlavy S, Hiramatsu L, Kučka M, Beluch WH, Naumann R, Skuplik I, Cobb J, Barton NH, Rolian C, Chan YF. An integrative genomic analysis of the Longshanks selection experiment for longer limbs in mice. eLife 2019; 8:e42014. [PMID: 31169497 PMCID: PMC6606024 DOI: 10.7554/elife.42014] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Accepted: 05/19/2019] [Indexed: 12/30/2022] Open
Abstract
Evolutionary studies are often limited by missing data that are critical to understanding the history of selection. Selection experiments, which reproduce rapid evolution under controlled conditions, are excellent tools to study how genomes evolve under selection. Here we present a genomic dissection of the Longshanks selection experiment, in which mice were selectively bred over 20 generations for longer tibiae relative to body mass, resulting in 13% longer tibiae in two replicates. We synthesized evolutionary theory, genome sequences and molecular genetics to understand the selection response and found that it involved both polygenic adaptation and discrete loci of major effect, with the strongest loci tending to be selected in parallel between replicates. We show that selection may favor de-repression of bone growth through inactivating two limb enhancers of an inhibitor, Nkx3-2. Our integrative genomic analyses thus show that it is possible to connect individual base-pair changes to the overall selection response.
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Affiliation(s)
- João PL Castro
- Friedrich Miescher Laboratory of the Max Planck SocietyTübingenGermany
| | | | | | | | - Layla Hiramatsu
- Friedrich Miescher Laboratory of the Max Planck SocietyTübingenGermany
| | - Marek Kučka
- Friedrich Miescher Laboratory of the Max Planck SocietyTübingenGermany
| | - William H Beluch
- Friedrich Miescher Laboratory of the Max Planck SocietyTübingenGermany
| | - Ronald Naumann
- Max Planck Institute for Molecular Cell Biology and GeneticsDresdenGermany
| | | | | | - Nicholas H Barton
- Institute of Science and Technology (IST) AustriaKlosterneuburgAustria
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5
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Thompson AC, Capellini TD, Guenther CA, Chan YF, Infante CR, Menke DB, Kingsley DM. A novel enhancer near the Pitx1 gene influences development and evolution of pelvic appendages in vertebrates. eLife 2018; 7:38555. [PMID: 30499775 PMCID: PMC6269122 DOI: 10.7554/elife.38555] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 11/12/2018] [Indexed: 12/29/2022] Open
Abstract
Vertebrate pelvic reduction is a classic example of repeated evolution. Recurrent loss of pelvic appendages in sticklebacks has previously been linked to natural mutations in a pelvic enhancer that maps upstream of Pitx1. The sequence of this upstream PelA enhancer is not conserved to mammals, so we have surveyed a large region surrounding the mouse Pitx1 gene for other possible hind limb control sequences. Here we identify a new pelvic enhancer, PelB, that maps downstream rather than upstream of Pitx1. PelB drives expression in the posterior portion of the developing hind limb, and deleting the sequence from mice alters the size of several hind limb structures. PelB sequences are broadly conserved from fish to mammals. A wild stickleback population lacking the pelvis has an insertion/deletion mutation that disrupts the structure and function of PelB, suggesting that changes in this ancient enhancer contribute to evolutionary modification of pelvic appendages in nature.
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Affiliation(s)
- Abbey C Thompson
- Department of Developmental Biology, Stanford University School of Medicine, California, United States.,Department of Genetics, Stanford University School of Medicine, California, United States
| | - Terence D Capellini
- Department of Developmental Biology, Stanford University School of Medicine, California, United States
| | - Catherine A Guenther
- Department of Developmental Biology, Stanford University School of Medicine, California, United States.,Howard Hughes Medical Institute, Stanford University, California, United States
| | - Yingguang Frank Chan
- Department of Developmental Biology, Stanford University School of Medicine, California, United States
| | - Carlos R Infante
- Department of Genetics, University of Georgia, Georgia, United States
| | - Douglas B Menke
- Department of Genetics, University of Georgia, Georgia, United States
| | - David M Kingsley
- Department of Developmental Biology, Stanford University School of Medicine, California, United States.,Howard Hughes Medical Institute, Stanford University, California, United States
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6
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Yang K, Kang J. Tissue Regeneration Enhancer Elements: A Way to Unlock Endogenous Healing Power. Dev Dyn 2018; 248:34-42. [PMID: 30291668 DOI: 10.1002/dvdy.24676] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Revised: 09/27/2018] [Accepted: 10/02/2018] [Indexed: 01/15/2023] Open
Abstract
Regenerative capacity is widespread throughout almost all animal phyla. However, the distribution pattern remains incompletely understood. Various examples show that very closely related species display different regenerative capacities. Why and how have diverse regenerative capacities evolved across species? One prevailing thought in the field of regeneration is that most regeneration-associated factors are evolutionarily conserved, suggesting the existence of an innate tissue regeneration ability in all species. However, its regulation is differentially controlled in distinct species, resulting in heterogeneous regenerative capabilities. In this review, we discuss regeneration-associated enhancers, the key cis-regulatory elements controlling gene expression, their underlying molecular mechanisms, and their influence on regenerative capacity. Understanding the regulatory mechanisms of regeneration enhancers can provide fundamental insights into tissue regeneration and further help us develop therapeutic strategies to unlock latent healing powers in humans. Developmental Dynamics 248:34-42, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- KaHoua Yang
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
| | - Junsu Kang
- Department of Cell and Regenerative Biology, University of Wisconsin School of Medicine and Public Health, University of Wisconsin-Madison, Madison, Wisconsin
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7
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Chen H, Capellini TD, Schoor M, Mortlock DP, Reddi AH, Kingsley DM. Heads, Shoulders, Elbows, Knees, and Toes: Modular Gdf5 Enhancers Control Different Joints in the Vertebrate Skeleton. PLoS Genet 2016; 12:e1006454. [PMID: 27902701 PMCID: PMC5130176 DOI: 10.1371/journal.pgen.1006454] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Accepted: 11/02/2016] [Indexed: 11/18/2022] Open
Abstract
Synovial joints are crucial for support and locomotion in vertebrates, and are the frequent site of serious skeletal defects and degenerative diseases in humans. Growth and differentiation factor 5 (Gdf5) is one of the earliest markers of joint formation, is required for normal joint development in both mice and humans, and has been genetically linked to risk of common osteoarthritis in Eurasian populations. Here, we systematically survey the mouse Gdf5 gene for regulatory elements controlling expression in synovial joints. We identify separate regions of the locus that control expression in axial tissues, in proximal versus distal joints in the limbs, and in remarkably specific sub-sets of composite joints like the elbow. Predicted transcription factor binding sites within Gdf5 regulatory enhancers are required for expression in particular joints. The multiple enhancers that control Gdf5 expression in different joints are distributed over a hundred kilobases of DNA, including regions both upstream and downstream of Gdf5 coding exons. Functional rescue tests in mice confirm that the large flanking regions are required to restore normal joint formation and patterning. Orthologs of these enhancers are located throughout the large genomic region previously associated with common osteoarthritis risk in humans. The large array of modular enhancers for Gdf5 provide a new foundation for studying the spatial specificity of joint patterning in vertebrates, as well as new candidates for regulatory regions that may also influence osteoarthritis risk in human populations. Joints, such as the hip and knee, are crucial for support and locomotion in animals, and are the frequent sites of serious human diseases such as arthritis. The Growth and differentiation factor 5 (Gdf5) gene is required for normal joint formation, and has been linked to risk of common arthritis in Eurasians. Here, we surveyed the mouse gene for the regulatory information that controls Gdf5's expression pattern in stripes at sites of joint formation. The gene does not have a single regulatory sequence that drives expression in all joints. Instead, Gdf5 has multiple different control sequences that show striking specificity for joints in the head, vertebral column, shoulder, elbow, wrist, hip, knee, and digits. Rescue experiments show that multiple control sequences are required to restore normal joint formation in Gdf5 mutants. The joint control sequences originally found in mice are also present in humans, where they are marked as active regions during fetal development and post-natal life, and map to a large region associated with arthritis risk in human populations. Regulatory variants in the human GDF5 control sequences can now be studied for their potential role in altering joint development or disease risk at particular locations in the skeleton.
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Affiliation(s)
- Hao Chen
- Department of Developmental Biology, Beckman Center B300, Stanford University School of Medicine, Stanford, California, United States of America
| | - Terence D. Capellini
- Department of Developmental Biology, Beckman Center B300, Stanford University School of Medicine, Stanford, California, United States of America
- Human Evolutionary Biology, Peabody Museum, Harvard University, Cambridge, Massachusetts, United States of America
- Broad Institute of MIT and Harvard, Cambridge, Massachusetts, United States of America
| | | | - Doug P. Mortlock
- Molecular Physiology and Biophysics and Vanderbilt Genetics Institute, Vanderbilt University, Nashville, Tennessee, United States of America
| | - A. Hari Reddi
- Center for Tissue Regeneration and Repair, University of California Davis Medical Center, Sacramento, California, United States of America
| | - David M. Kingsley
- Department of Developmental Biology, Beckman Center B300, Stanford University School of Medicine, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford University, Stanford, California, United States of America
- * E-mail:
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8
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Guenther CA, Wang Z, Li E, Tran MC, Logan CY, Nusse R, Pantalena-Filho L, Yang GP, Kingsley DM. A distinct regulatory region of the Bmp5 locus activates gene expression following adult bone fracture or soft tissue injury. Bone 2015; 77:31-41. [PMID: 25886903 PMCID: PMC4447581 DOI: 10.1016/j.bone.2015.04.010] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Revised: 04/02/2015] [Accepted: 04/04/2015] [Indexed: 12/25/2022]
Abstract
Bone morphogenetic proteins (BMPs) are key signaling molecules required for normal development of bones and other tissues. Previous studies have shown that null mutations in the mouse Bmp5 gene alter the size, shape and number of multiple bone and cartilage structures during development. Bmp5 mutations also delay healing of rib fractures in adult mutants, suggesting that the same signals used to pattern embryonic bone and cartilage are also reused during skeletal regeneration and repair. Despite intense interest in BMPs as agents for stimulating bone formation in clinical applications, little is known about the regulatory elements that control developmental or injury-induced BMP expression. To compare the DNA sequences that activate gene expression during embryonic bone formation and following acute injuries in adult animals, we assayed regions surrounding the Bmp5 gene for their ability to stimulate lacZ reporter gene expression in transgenic mice. Multiple genomic fragments, distributed across the Bmp5 locus, collectively coordinate expression in discrete anatomic domains during normal development, including in embryonic ribs. In contrast, a distinct regulatory region activated expression following rib fracture in adult animals. The same injury control region triggered gene expression in mesenchymal cells following tibia fracture, in migrating keratinocytes following dorsal skin wounding, and in regenerating epithelial cells following lung injury. The Bmp5 gene thus contains an "injury response" control region that is distinct from embryonic enhancers, and that is activated by multiple types of injury in adult animals.
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Affiliation(s)
- Catherine A Guenther
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Zhen Wang
- Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Emma Li
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Misha C Tran
- Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA
| | - Catriona Y Logan
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Roel Nusse
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA
| | - Luiz Pantalena-Filho
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA
| | - George P Yang
- Department of Surgery, Stanford University School of Medicine, Stanford, CA, USA; Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA.
| | - David M Kingsley
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, CA, USA; Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, CA, USA.
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9
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Infante CR, Park S, Mihala AG, Kingsley DM, Menke DB. Pitx1 broadly associates with limb enhancers and is enriched on hindlimb cis-regulatory elements. Dev Biol 2012. [PMID: 23201014 DOI: 10.1016/j.ydbio.2012.11.017] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Extensive functional analyses have demonstrated that the pituitary homeodomain transcription factor Pitx1 plays a critical role in specifying hindlimb morphology in vertebrates. However, much less is known regarding the target genes and cis-regulatory elements through which Pitx1 acts. Earlier studies suggested that the hindlimb transcription factors Tbx4, HoxC10, and HoxC11 might be transcriptional targets of Pitx1, but definitive evidence for direct regulatory interactions has been lacking. Using ChIP-Seq on embryonic mouse hindlimbs, we have pinpointed the genome-wide location of Pitx1 binding sites during mouse hindlimb development and identified potential gene targets for Pitx1. We determined that Pitx1 binding is significantly enriched near genes involved in limb morphogenesis, including Tbx4, HoxC10, and HoxC11. Notably, Pitx1 is bound to the previously identified HLEA and HLEB hindlimb enhancers of the Tbx4 gene and to a newly identified Tbx2 hindlimb enhancer. Moreover, Pitx1 binding is significantly enriched on hindlimb relative to forelimb-specific cis-regulatory features that are differentially marked by H3K27ac. However, our analysis revealed that Pitx1 also strongly associates with many functionally verified limb enhancers that exhibit similar levels of activity in the embryonic mesenchyme of forelimbs and hindlimbs. We speculate that Pitx1 influences hindlimb morphology both through the activation of hindlimb-specific enhancers as well as through the hindlimb-specific modulation of enhancers that are active in both sets of limbs.
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Affiliation(s)
- Carlos R Infante
- Department of Genetics, University of Georgia, Coverdell Building, Room 250A, 500 DW Brooks Drive, Athens, GA 30602, USA
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10
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Rodriguez-Fontenla C, Carr A, Gomez-Reino JJ, Tsezou A, Loughlin J, Gonzalez A. Association of a BMP5 microsatellite with knee osteoarthritis: case-control study. Arthritis Res Ther 2012. [PMID: 23186552 PMCID: PMC3674626 DOI: 10.1186/ar4102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Introduction We aimed to explore the involvement of a multiallelic functional polymorphism in knee osteoarthritis (OA) susceptibility as a prototype of possible genetic factors escaping GWAS detection. Methods OA patients and controls from three European populations (Greece, Spain and the UK) adding up to 1003 patients (716 women, 287 men) that had undergone total knee joint replacement (TKR) due to severe primary OA and 1543 controls (758 women, 785 men) lacking clinical signs or symptoms of OA were genotyped for the D6S1276 microsatellite in intron 1 of BMP5. Genotype and mutiallelic trend tests were used to compare cases and controls. Results Significant association was found between the microsatellite and knee OA in women (P from 3.1 x10-4 to 4.1 x10-4 depending on the test), but not in men. Three of the alleles showed significant differences between patients and controls, one of them of increased risk and two of protection. The gender association and the allele direction of change were very concordant with those previously reported for hip OA. Conclusions We have found association of knee OA in women with the D6S1276 functional microsatellite that modifies in cis the expression of BMP5 making this a sounder OA genetic factor and extending its involvement to other joints. This result also shows the interest of analysing other multiallelic polymorphisms.
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11
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Leclerc D, Cao Y, Deng L, Mikael LG, Wu Q, Rozen R. Differential gene expression and methylation in the retinoid/PPARA pathway and of tumor suppressors may modify intestinal tumorigenesis induced by low folate in mice. Mol Nutr Food Res 2012; 57:686-97. [PMID: 23001810 DOI: 10.1002/mnfr.201200212] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 06/20/2012] [Accepted: 06/25/2012] [Indexed: 01/01/2023]
Abstract
SCOPE Inadequate folate intake increases risk for colorectal cancer. We previously showed that low-folate diets induced intestinal tumors in BALB/c mice, but not in C57BL/6 mice. We suggested that DNA damage, altered methylation, and reduced apoptosis could contribute to tumorigenesis in this model. METHODS AND RESULTS To identify genes involved in tumorigenesis, we compared gene expression profiles in preneoplastic intestine of BALB/c and C57BL/6 mice-fed low folate. We identified 74 upregulated and 90 downregulated genes in BALB/c compared to C57BL/6 mice. We validated decreased expression of Bcmo1 and increased expression of Aldh1a, which would be expected to upregulate the peroxisome proliferator-activated receptor alpha (PPARA) pathway, and confirmed the expected upregulation of several Ppara downstream genes. We verified, in BALB/c mice, reduced expression of Sprr2a, a gene that increases resistance to oxidative damage, and of two oncosuppressors (Bmp5 and Arntl). Low folate increased Ppara and Aldh1a1 expression, and decreased Bcmo1, Sprr2a, and Bmp5 expression in BALB/c, compared to BALB/c on control diets. Bcmo1, Ppara, and Bmp5 showed differential DNA methylation related to strain, diet, and/or Mthfr genotype. CONCLUSION Disturbed regulation of the retinoid/PPARA pathway, which influences oxidative damage, and altered expression of tumor suppressors may contribute to intestinal tumorigenesis induced by low-folate intake.
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Affiliation(s)
- Daniel Leclerc
- Department of Human Genetics, Montreal Children's Hospital Research Institute, McGill University, Montreal, Canada
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12
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Mutation of Rubie, a novel long non-coding RNA located upstream of Bmp4, causes vestibular malformation in mice. PLoS One 2012; 7:e29495. [PMID: 22253730 PMCID: PMC3257225 DOI: 10.1371/journal.pone.0029495] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2011] [Accepted: 11/29/2011] [Indexed: 12/02/2022] Open
Abstract
Background The vestibular apparatus of the vertebrate inner ear uses three fluid-filled semicircular canals to sense angular acceleration of the head. Malformation of these canals disrupts the sense of balance and frequently causes circling behavior in mice. The Epistatic circler (Ecl) is a complex mutant derived from wildtype SWR/J and C57L/J mice. Ecl circling has been shown to result from the epistatic interaction of an SWR-derived locus on chromosome 14 and a C57L-derived locus on chromosome 4, but the causative genes have not been previously identified. Methodology/Principal Findings We developed a mouse chromosome substitution strain (CSS-14) that carries an SWR/J chromosome 14 on a C57BL/10J genetic background and, like Ecl, exhibits circling behavior due to lateral semicircular canal malformation. We utilized CSS-14 to identify the chromosome 14 Ecl gene by positional cloning. Our candidate interval is located upstream of bone morphogenetic protein 4 (Bmp4) and contains an inner ear-specific, long non-coding RNA that we have designated Rubie (RNA upstream of Bmp4 expressed in inner ear). Rubie is spliced and polyadenylated, and is expressed in developing semicircular canals. However, we discovered that the SWR/J allele of Rubie is disrupted by an intronic endogenous retrovirus that causes aberrant splicing and premature polyadenylation of the transcript. Rubie lies in the conserved gene desert upstream of Bmp4, within a region previously shown to be important for inner ear expression of Bmp4. We found that the expression patterns of Bmp4 and Rubie are nearly identical in developing inner ears. Conclusions/Significance Based on these results and previous studies showing that Bmp4 is essential for proper vestibular development, we propose that Rubie is the gene mutated in Ecl mice, that it is involved in regulating inner ear expression of Bmp4, and that aberrant Bmp4 expression contributes to the Ecl phenotype.
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Abstract
Transcriptional regulation of gene expression plays a significant role in establishing the diversity of human cell types and biological functions from a common set of genes. The components of regulatory control in the human genome include cis-acting elements that act across immense genomic distances to influence the spatial and temporal distribution of gene expression. Here we review the established categories of distant-acting regulatory elements, discussing the classical and contemporary evidence of their regulatory potential and clinical importance. Current efforts to identify regulatory sequences throughout the genome and elucidate their biological significance depend heavily on advances in sequence conservation-based analyses and on increasingly large-scale efforts applying transgenic technologies in model organisms. We discuss the advantages and limitations of sequence conservation as a predictor of regulatory function and present complementary emerging technologies now being applied to annotate regulatory elements in vertebrate genomes.
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Affiliation(s)
- James P Noonan
- Department of Genetics, Yale University School of Medicine, New Haven, CT 06510, USA.
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14
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Wilkins JM, Southam L, Mustafa Z, Chapman K, Loughlin J. Association of a functional microsatellite within intron 1 of the BMP5 gene with susceptibility to osteoarthritis. BMC MEDICAL GENETICS 2009; 10:141. [PMID: 20021689 PMCID: PMC2807860 DOI: 10.1186/1471-2350-10-141] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/07/2009] [Accepted: 12/19/2009] [Indexed: 01/28/2023]
Abstract
Background In a previous study carried out by our group, the genotyping of 36 microsatellite markers from within a narrow interval of chromosome 6p12.3-q13 generated evidence for linkage and for association to female hip osteoarthritis (OA), with the most compelling association found for a marker within intron 1 of the bone morphogenetic protein 5 gene (BMP5). In this study, we aimed to further categorize the association of variants within intron 1 of BMP5 with OA through an expanded genetic association study of the intron and subsequent functional analysis of associated polymorphisms. Methods We genotyped 18 common polymorphisms including 8 microsatellites and 9 single nucleotide polymorphisms (SNPs) and 1 insertion/deletion (INDEL) from within highly conserved regions between human and mouse within intron 1 of BMP5. These markers were then tested for association to OA by a two-stage approach in which the polymorphisms were initially genotyped in a case-control cohort comprising 361 individuals with associated polymorphisms (P ≤ 0.05) then genotyped in a second case-control cohort comprising 1185 individuals. Results Two BMP5 intron 1 polymorphisms demonstrated association in the combined case-control cohort of 1546 individuals (765 cases and 781 controls): microsatellite D6S1276 (P = 0.018) and SNP rs921126 (P = 0.013). Functional analyses in osteoblastic, chondrocytic, and adipocytic cell lines indicated that allelic variants of D6S1276 have significant effects on the transcriptional activity of the BMP5 promoter in vitro. Conclusion Variability in gene expression of BMP5 may be an important contributor to OA genetic susceptibility.
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Affiliation(s)
- James M Wilkins
- University of Oxford, Institute of Musculoskeletal Sciences, Botnar Research Centre, Nuffield Orthopaedic Centre, Oxford, OX3 7LD, UK.
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Abstract
Much evidence suggests that "developmental regulator" genes, like those encoding transcription factors and signaling molecules, are typically controlled by many modular, tissue-specific cis-regulatory elements that function during embryogenesis. These elements are often far from gene coding regions and promoters. Bone morphogenetic proteins (BMPs) drive many processes in development relating to organogenesis and differentiation. Four BMP family members, Bmp2, Bmp4, Bmp5, and Gdf6, are now known to be under the control of distant cis-regulatory elements. BMPs are thus firmly placed in the category of genes prone to this phenomenon. The analysis of distant BMP regulatory elements has provided insight into the many pleiotropic effects of BMP genes, and underscores the biological importance of non-coding genomic DNA elements.
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16
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Chandler KJ, Chandler RL, Mortlock DP. Identification of an ancient Bmp4 mesoderm enhancer located 46 kb from the promoter. Dev Biol 2009; 327:590-602. [PMID: 19159624 DOI: 10.1016/j.ydbio.2008.12.033] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2008] [Revised: 12/19/2008] [Accepted: 12/22/2008] [Indexed: 01/19/2023]
Abstract
Bone morphogenetic protein 4 (Bmp4) is a multi-functional, developmentally regulated gene that is essential for mouse development, as most Bmp4-null mouse embryos die at the onset of gastrulation and fail to develop mesoderm. Little is known about the transcriptional regulation of Bmp4. To identify potential long-range cis-regulatory elements that direct its complex spatiotemporal expression patterns, we surveyed the mouse Bmp4 locus using two overlapping bacterial artificial chromosome (BAC) reporter transgenes. Our findings indicate that tissue-specific cis-regulatory elements reside greater than 28 kb 5' or 3' to the mouse Bmp4 transcription unit. In addition, comparative analyses identified three noncoding evolutionarily conserved regions (ECRs), spaced around the gene and conserved from mammals to fish, that are maintained in a syntenic group across vertebrates. Deletion of one of these conserved sequences (ECR2) from a BAC transgene revealed a tissue-specific requirement for ECR2 in driving Bmp4 expression in extraembryonic and embryonic mesoderm. Furthermore, a 467 bp mouse sequence containing ECR2 reproducibly directed lacZ minigene expression in mesoderm. Taken together, this shows that an ancient, mesoderm-specific cis-regulatory element resides nearly 50 kb 5' to mouse Bmp4.
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Affiliation(s)
- Kelly J Chandler
- Department of Molecular Physiology and Biophysics, Center for Human Genetics Research, Vanderbilt University School of Medicine, 1175 MRBIV, 2215 Garland Avenue, Nashville, TN 37232, USA
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Guenther C, Pantalena-Filho L, Kingsley DM. Shaping skeletal growth by modular regulatory elements in the Bmp5 gene. PLoS Genet 2008; 4:e1000308. [PMID: 19096511 PMCID: PMC2592695 DOI: 10.1371/journal.pgen.1000308] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2008] [Accepted: 11/14/2008] [Indexed: 11/18/2022] Open
Abstract
Cartilage and bone are formed into a remarkable range of shapes and sizes that underlie many anatomical adaptations to different lifestyles in vertebrates. Although the morphological blueprints for individual cartilage and bony structures must somehow be encoded in the genome, we currently know little about the detailed genomic mechanisms that direct precise growth patterns for particular bones. We have carried out large-scale enhancer surveys to identify the regulatory architecture controlling developmental expression of the mouse Bmp5 gene, which encodes a secreted signaling molecule required for normal morphology of specific skeletal features. Although Bmp5 is expressed in many skeletal precursors, different enhancers control expression in individual bones. Remarkably, we show here that different enhancers also exist for highly restricted spatial subdomains along the surface of individual skeletal structures, including ribs and nasal cartilages. Transgenic, null, and regulatory mutations confirm that these anatomy-specific sequences are sufficient to trigger local changes in skeletal morphology and are required for establishing normal growth rates on separate bone surfaces. Our findings suggest that individual bones are composite structures whose detailed growth patterns are built from many smaller lineage and gene expression domains. Individual enhancers in BMP genes provide a genomic mechanism for controlling precise growth domains in particular cartilages and bones, making it possible to separately regulate skeletal anatomy at highly specific locations in the body. Every bone in the skeleton has a specific shape and size. These characteristic features must be under separate genetic control, because individual bones can undergo striking morphological changes in different species. Researchers have long postulated that the morphology of individual bones arises from the local activity of many separate growth domains around each bone's surface. Differential growth within such domains could modify size, curvature, and formation of specific processes. Here, we show that local growth domains around individual bones are controlled by independent regulatory sequences in bone morphogenetic protein (BMP) genes. We identify multiple regulatory sequences in the Bmp5 gene that control expression in particular bones, rather than all bones. We show that some of these elements are remarkably specific for individual subdomains around the surface of individual bones. Finally, we show that local BMP signaling is necessary and sufficient to trigger highly localized growth patterns in ribs and nasal cartilages. These results suggest that the detailed pattern of growth of individual skeletal structures is encoded in part by multiple regulatory sequences in BMP genes. Gain and loss of anatomy-specific sequences in BMP genes may provide a flexible genomic mechanism for modifying local skeletal anatomy during vertebrate evolution.
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Affiliation(s)
- Catherine Guenther
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California, United States of America
| | - Luiz Pantalena-Filho
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California, United States of America
| | - David M. Kingsley
- Department of Developmental Biology, Stanford University School of Medicine, Stanford, California, United States of America
- Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California, United States of America
- * E-mail:
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18
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Menke DB, Guenther C, Kingsley DM. Dual hindlimb control elements in the Tbx4 gene and region-specific control of bone size in vertebrate limbs. Development 2008; 135:2543-53. [DOI: 10.1242/dev.017384] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The Tbx4 transcription factor is crucial for normal hindlimb and vascular development, yet little is known about how its highly conserved expression patterns are generated. We have used comparative genomics and functional scanning in transgenic mice to identify a dispersed group of enhancers controlling Tbx4 expression in different tissues. Two independent enhancers control hindlimb expression, one located upstream and one downstream of the Tbx4 coding exons. These two enhancers, hindlimb enhancer A and hindlimb enhancer B (HLEA and HLEB), differ in their primary sequence, in their precise patterns of activity within the hindlimb, and in their degree of sequence conservation across animals. HLEB is highly conserved from fish to mammals. Although Tbx4 expression and hindlimb development occur at different axial levels in fish and mammals, HLEB cloned from either fish or mouse is capable of driving expression at the appropriate position of hindlimb development in mouse embryos. HLEA is highly conserved only in mammals. Deletion of HLEA from the endogenous mouse locus reduces expression of Tbx4 in the hindlimb during embryogenesis, bypasses the embryonic lethality of Tbx4-null mutations, and produces viable, fertile mice with characteristic changes in the size of bones in the hindlimb but not the forelimb. We speculate that dual hindlimb enhancers provide a flexible genomic mechanism for altering the strength and location of Tbx4 expression during normal development, making it possible to separately modify the size of forelimb and hindlimb bones during vertebrate evolution.
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Affiliation(s)
- Douglas B. Menke
- Howard Hughes Medical Institute and Department of Developmental Biology,Stanford University, Stanford, CA 94305-5329, USA
| | - Catherine Guenther
- Howard Hughes Medical Institute and Department of Developmental Biology,Stanford University, Stanford, CA 94305-5329, USA
| | - David M. Kingsley
- Howard Hughes Medical Institute and Department of Developmental Biology,Stanford University, Stanford, CA 94305-5329, USA
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19
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Fogelgren B, Kuroyama MC, McBratney-Owen B, Spence AA, Melahn LE, Anawati MK, Cabatbat C, Alarcon VB, Marikawa Y, Lozanoff S. Misexpression of Six2 is associated with heritable frontonasal dysplasia and renal hypoplasia in 3H1 Br mice. Dev Dyn 2008; 237:1767-79. [PMID: 18570229 PMCID: PMC2955765 DOI: 10.1002/dvdy.21587] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Abstract
A radiation-induced mouse mutant, Brachyrrhine (Br), exhibits frontonasal dysplasia and renal hypoplasia, two malformations associated with deficiencies in mesenchymal condensation. The purpose of this study was to resolve the Br locus, evaluate possible candidate genes, and identify developmental defects in the mutant chondrocranium. Linkage analysis mapped the Br mutation to a critical region distal to D17Mit76, which contains only one gene, the transcription factor Six2. Sequence analysis of the Six2 gene, including 1.5 kb of the promoter, failed to reveal the Br mutation. However, homozygous Br/Br embryos showed almost complete absence of Six2 mRNA and protein in craniofacial and renal tissues while heterozygous Br/+ embryos displayed intermediate Six2 levels. Mutant embryos displayed malformations of neural crest-derived structures of the anterior cranium where Six2 is normally expressed. These data suggest a mutation in a novel cis-acting regulatory region inhibits Six2 expression and is associated with frontonasal dysplasia and renal hypoplasia.
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Affiliation(s)
- Ben Fogelgren
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Mari C. Kuroyama
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | | | - Allyson A. Spence
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Laura E. Melahn
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Mireille K. Anawati
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Chantelle Cabatbat
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Vernadeth B. Alarcon
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Yusuke Marikawa
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
| | - Scott Lozanoff
- Department of Anatomy, Biochemistry, and Physiology, University of Hawai’i School of Medicine, Honolulu, HI 98613
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20
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Ho AM, Marker PC, Peng H, Quintero AJ, Kingsley DM, Huard J. Dominant negative Bmp5 mutation reveals key role of BMPs in skeletal response to mechanical stimulation. BMC DEVELOPMENTAL BIOLOGY 2008; 8:35. [PMID: 18380899 PMCID: PMC2335095 DOI: 10.1186/1471-213x-8-35] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Accepted: 04/01/2008] [Indexed: 11/11/2022]
Abstract
Background Over a hundred years ago, Wolff originally observed that bone growth and remodeling are exquisitely sensitive to mechanical forces acting on the skeleton. Clinical studies have noted that the size and the strength of bone increase with weight bearing and muscular activity and decrease with bed rest and disuse. Although the processes of mechanotransduction and functional response of bone to mechanical strain have been extensively studied, the molecular signaling mechanisms that mediate the response of bone cells to mechanical stimulation remain unclear. Results Here, we identify a novel germline mutation at the mouse Bone morphogenetic protein 5 (Bmp5) locus. Genetic analysis shows that the mutation occurs at a site encoding the proteolytic processing sequence of the BMP5 protein and blocks proper processing of BMP5. Anatomic studies reveal that this mutation affects the formation of multiple skeletal features including several muscle-induced skeletal sites in vivo. Biomechanical studies of osteoblasts from these anatomic sites show that the mutation inhibits the proper response of bone cells to mechanical stimulation. Conclusion The results from these genetic, biochemical, and biomechanical studies suggest that BMPs are required not only for skeletal patterning during embryonic development, but also for bone response and remodeling to mechanical stimulation at specific anatomic sites in the skeleton.
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Affiliation(s)
- Andrew M Ho
- Department of Developmental Biology and Howard Hughes Medical Institute, Beckman Center B300, Stanford University School of Medicine, Stanford, California 94305, USA.
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21
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Kleinjan DA, Lettice LA. Long-range gene control and genetic disease. ADVANCES IN GENETICS 2008; 61:339-88. [PMID: 18282513 DOI: 10.1016/s0065-2660(07)00013-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The past two decades have seen great progress in the elucidation of the genetic basis of human genetic disease. Many clinical phenotypes have been linked with mutations or deletions in specific causative genes. However, it is often less recognized that in addition to the integrity of the protein-coding sequences, human health critically also depends on the spatially, temporally, and quantitatively correct expression of those genes. Genetic disease can therefore equally be caused by disruption of the regulatory mechanisms that ensure proper gene expression. The term "position effect" is used in those situations where the expression level of a gene is deleteriously affected by an alteration in its chromosomal environment, while maintaining an intact transcription unit. Here, we review recent advances in our understanding of the possible mechanisms of a number of "position effect" disease cases and discuss the findings with respect to current models for genome organization and long-range control of gene expression.
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Affiliation(s)
- Dirk A Kleinjan
- MRC Human Genetics Unit, Western General Hospital, Edinburgh EH4 2XU, United Kingdom
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22
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Mailhot G, Yang M, Mason-Savas A, Mackay CA, Leav I, Odgren PR. BMP-5 expression increases during chondrocyte differentiation in vivo and in vitro and promotes proliferation and cartilage matrix synthesis in primary chondrocyte cultures. J Cell Physiol 2007; 214:56-64. [PMID: 17541940 PMCID: PMC2750834 DOI: 10.1002/jcp.21164] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Bone morphogenetic proteins (BMPs) play pivotal roles in bone and cartilage growth and repair. Through phenotypes of short-ear (se) mice, which have BMP-5 mutations, a role for BMP-5 in some specific aspects of skeletogenesis and cartilage growth is known. This report examines BMP-5 expression in the growth plate and in differentiating cultures of primary chondrocytes, and the effects of addition of BMP-5 or its inhibition by anti-BMP-5 antibody in chondrocyte cultures. By laser capture microdissection and immunohistochemistry, we found that BMP-5 is expressed in proliferating zone (PZ) chondrocytes and that the expression increases sharply with hypertrophic differentiation. A similar pattern was observed in differentiating cultures of primary chondrocytes, with BMP-5 expression increasing as cells differentiated, in contrast to other BMPs. BMP-5 added to cultures increased cell proliferation early in the culture period and also stimulated cartilage matrix synthesis. Also, BMP-5 addition to the cultures activated phosphorylation of Smad 1/5/8 and p38 MAP kinase and caused increased nuclear accumulation of phospho-Smads. Anti-BMP-5 antibody inhibited the endogenous BMP-5, reducing cell proliferation and phospho-Smad nuclear accumulation. Together, the results demonstrate that BMP-5 is normally an important regulator of chondrocyte proliferation and differentiation. Whether other BMPs may compensate in BMP-5 loss-of-function mutations is discussed.
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Affiliation(s)
- Geneviève Mailhot
- Department of Cell Biology, University of Massachusetts Medical School, Worcester, USA
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23
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Lehoczky JA, Innis JW. A mouse transgene drives embryonic dorsal posterior commissure expression. Transgenic Res 2007; 16:823-8. [PMID: 17549599 DOI: 10.1007/s11248-007-9104-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2007] [Accepted: 05/10/2007] [Indexed: 11/27/2022]
Abstract
In this report we generated mice co-transgenic for a minimal promoter LacZ construct and a mouse BAC from the gene poor region upstream of the Hoxd cluster. In addition to expression in the distal limb, genital bud, and spinal cord, we show that this BAC transgene also reproducibly drives unique bilateral, dorsal posterior commissure expression. The ability of this BAC to direct posterior commissure expression makes it worthy of further study as a valuable tool in transgenic/targeting experiments.
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Affiliation(s)
- Jessica A Lehoczky
- Department of Human Genetics, University of Michigan, Ann Arbor, MI 48109-0618, USA
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Boyle S, Misfeldt A, Chandler KJ, Deal KK, Southard-Smith EM, Mortlock DP, Baldwin HS, de Caestecker M. Fate mapping using Cited1-CreERT2 mice demonstrates that the cap mesenchyme contains self-renewing progenitor cells and gives rise exclusively to nephronic epithelia. Dev Biol 2007; 313:234-45. [PMID: 18061157 DOI: 10.1016/j.ydbio.2007.10.014] [Citation(s) in RCA: 209] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2007] [Revised: 10/15/2007] [Accepted: 10/16/2007] [Indexed: 12/20/2022]
Abstract
Classic tissue recombination and in vitro lineage tracing studies suggest that condensed metanephric mesenchyme (MM) gives rise to nephronic epithelium of the adult kidney. However, these studies do not distinguish between cap mesenchyme and pre-tubular aggregates comprising the condensed MM, nor do they establish whether these cells have self-renewing capacity. To address these questions, we generated Cited1-CreER(T2) BAC transgenic mice, which express tamoxifen-regulated Cre recombinase exclusively in the cap mesenchyme. Fate mapping was performed by crossing these mice with the Rosa26R(LacZ) reporter line and evaluating the location and cellular characteristics of LacZ positive cells at different time points following tamoxifen injection. These studies confirmed expected results from previous in vitro analysis of MM cell fate, and provide in vivo evidence that the cap mesenchyme does not contribute to collecting duct epithelium in the adult. Furthermore, by exploiting the temporally regulated Cre recombinase, these studies show that nephronic epithelium arising at different stages of nephrogenesis has distinct spatial distribution in the adult kidney, and demonstrate for the first time that the cap mesenchyme includes a population of self-renewing epithelial progenitor cells.
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Affiliation(s)
- Scott Boyle
- Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN 37232-2372, USA
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25
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Feldman GJ, Billings PC, Patel RV, Caron RJ, Guenther C, Kingsley DM, Kaplan FS, Shore EM. Over-expression of BMP4 and BMP5 in a child with axial skeletal malformations and heterotopic ossification: a new syndrome. Am J Med Genet A 2007; 143A:699-706. [PMID: 17345627 DOI: 10.1002/ajmg.a.31649] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Bone morphogenetic proteins (BMPs) are a highly conserved class of signaling molecules that induce ectopic cartilage and bone formation in vivo. Dysregulated expression of bone morphogenetic protein 4 (BMP4) is found in the cells of patients who have fibrodysplasia ossificans progressiva (FOP), a genetic disorder of axial and appendicular skeletal malformation and progressive heterotopic ossification. Loss of function mutations in the bone morphogenetic protein 5 (bmp5) gene leading to under-expression of BMP5 cause the murine short ear syndrome, characterized by small malformed ears and a broad range of axial skeletal malformations. We found features reminiscent of both the short ear mouse and FOP in a child with malformed external ears, multiple malformations of the axial skeleton, and progressive heterotopic ossification in the neck and back. We examined BMP mRNA expression in transformed lymphocytes by semi-quantitative RT-PCR and protein expression by ELISA assays and immunohistochemistry. Elevated levels of BMP4 and BMP5 mRNA and protein were detected in the patient's cells while levels of BMP2 mRNA were unchanged. Our data suggest that dysregulated expression of BMP4 and BMP5 genes is associated with an array of human axial skeletal abnormalities similar to the short ear mouse and FOP.
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Affiliation(s)
- George J Feldman
- Department of Orthopaedic Surgery, Center for Research in FOP and Related Disorders, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA
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Spagnoli A, O'Rear L, Chandler RL, Granero-Molto F, Mortlock DP, Gorska AE, Weis JA, Longobardi L, Chytil A, Shimer K, Moses HL. TGF-beta signaling is essential for joint morphogenesis. ACTA ACUST UNITED AC 2007; 177:1105-17. [PMID: 17576802 PMCID: PMC2064369 DOI: 10.1083/jcb.200611031] [Citation(s) in RCA: 124] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Despite its clinical significance, joint morphogenesis is still an obscure process. In this study, we determine the role of transforming growth factor beta (TGF-beta) signaling in mice lacking the TGF-beta type II receptor gene (Tgfbr2) in their limbs (Tgfbr2(PRX-1KO)). In Tgfbr2(PRX-1KO) mice, the loss of TGF-beta responsiveness resulted in the absence of interphalangeal joints. The Tgfbr2(Prx1KO) joint phenotype is similar to that in patients with symphalangism (SYM1-OMIM185800). By generating a Tgfbr2-green fluorescent protein-beta-GEO-bacterial artificial chromosome beta-galactosidase reporter transgenic mouse and by in situ hybridization and immunofluorescence, we determined that Tgfbr2 is highly and specifically expressed in developing joints. We demonstrated that in Tgfbr2(PRX-1KO) mice, the failure of joint interzone development resulted from an aberrant persistence of differentiated chondrocytes and failure of Jagged-1 expression. We found that TGF-beta receptor II signaling regulates Noggin, Wnt9a, and growth and differentiation factor-5 joint morphogenic gene expressions. In Tgfbr2(PRX-1KO) growth plates adjacent to interphalangeal joints, Indian hedgehog expression is increased, whereas Collagen 10 expression decreased. We propose a model for joint development in which TGF-beta signaling represents a means of entry to initiate the process.
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Affiliation(s)
- Anna Spagnoli
- Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
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27
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Bolton EC, So AY, Chaivorapol C, Haqq CM, Li H, Yamamoto KR. Cell- and gene-specific regulation of primary target genes by the androgen receptor. Genes Dev 2007; 21:2005-17. [PMID: 17699749 PMCID: PMC1948856 DOI: 10.1101/gad.1564207] [Citation(s) in RCA: 255] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2007] [Accepted: 07/06/2007] [Indexed: 01/08/2023]
Abstract
The androgen receptor (AR) mediates the physiologic and pathophysiologic effects of androgens including sexual differentiation, prostate development, and cancer progression by binding to genomic androgen response elements (AREs), which influence transcription of AR target genes. The composition and context of AREs differ between genes, thus enabling AR to confer multiple regulatory functions within a single nucleus. We used expression profiling of an immortalized human prostate epithelial cell line to identify 205 androgen-responsive genes (ARGs), most of them novel. In addition, we performed chromatin immunoprecipitation to identify 524 AR binding regions and validated in reporter assays the ARE activities of several such regions. Interestingly, 67% of our AREs resided within approximately 50 kb of the transcription start sites of 84% of our ARGs. Indeed, most ARGs were associated with two or more AREs, and ARGs were sometimes themselves linked in gene clusters containing up to 13 AREs and 12 ARGs. AREs appeared typically to be composite elements, containing AR binding sequences adjacent to binding motifs for other transcriptional regulators. Functionally, ARGs were commonly involved in prostate cell proliferation, communication, differentiation, and possibly cancer progression. Our results provide new insights into cell- and gene-specific mechanisms of transcriptional regulation of androgen-responsive gene networks.
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Affiliation(s)
- Eric C. Bolton
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94143, USA
| | - Alex Y. So
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94143, USA
- Chemistry and Chemical Biology Graduate Program, University of California, San Francisco, California 94143, USA
| | - Christina Chaivorapol
- Department of Biochemistry and Biophysics, University of California, San Francisco, California 94143, USA
- California Institute for Quantitative Biomedical Research, University of California, San Francisco, California 94143, USA
- Graduate Program in Biological and Medical Informatics, University of California, San Francisco, California 94143, USA
| | - Christopher M. Haqq
- Department of Urology, University of California, San Francisco, California 94143, USA
| | - Hao Li
- Department of Biochemistry and Biophysics, University of California, San Francisco, California 94143, USA
- California Institute for Quantitative Biomedical Research, University of California, San Francisco, California 94143, USA
- Graduate Program in Biological and Medical Informatics, University of California, San Francisco, California 94143, USA
| | - Keith R. Yamamoto
- Department of Cellular and Molecular Pharmacology, University of California, San Francisco, California 94143, USA
- Chemistry and Chemical Biology Graduate Program, University of California, San Francisco, California 94143, USA
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28
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Noel EE, Ragavan N, Walsh MJ, James SY, Matanhelia SS, Nicholson CM, Lu YJ, Martin FL. Differential gene expression in the peripheral zone compared to the transition zone of the human prostate gland. Prostate Cancer Prostatic Dis 2007; 11:173-80. [PMID: 17646851 DOI: 10.1038/sj.pcan.4500997] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Gene expression profiles may lend insight into whether prostate adenocarcinoma (CaP) predominantly occurs in the peripheral zone (PZ) compared to the transition zone (TZ). From human prostates, tissue sets consisting of PZ and TZ were isolated to investigate whether there is a differential level of gene expression between these two regions of this gland. Gene expression profiling using Affymetrix Human Genome U133 plus 2.0 arrays coupled with quantitative real-time reverse transcriptase-PCR was employed. Genes associated with neurogenesis, signal transduction, embryo implantation and cell adhesion were found to be expressed at a higher level in the PZ. Those overexpressed in the TZ were associated with neurogenesis development, signal transduction, cell motility and development. Whether such differential gene expression profiles may identify molecular mechanisms responsible for susceptibility to CaP remains to be ascertained.
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Affiliation(s)
- E E Noel
- Medical Oncology Centre, Institute of Cancer, Barts and London School of Medicine and Dentistry Queen Mary, University of London, London, UK
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Chandler RL, Chandler KJ, McFarland KA, Mortlock DP. Bmp2 transcription in osteoblast progenitors is regulated by a distant 3' enhancer located 156.3 kilobases from the promoter. Mol Cell Biol 2007; 27:2934-51. [PMID: 17283059 PMCID: PMC1899916 DOI: 10.1128/mcb.01609-06] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2006] [Revised: 10/16/2006] [Accepted: 01/22/2007] [Indexed: 11/20/2022] Open
Abstract
Bone morphogenetic protein 2 (encoded by Bmp2) has been implicated as an important signaling ligand for osteoblast differentiation and bone formation and as a genetic risk factor for osteoporosis. To initially survey a large genomic region flanking the mouse Bmp2 gene for cis-regulatory function, two bacterial artificial chromosome (BAC) clones that extend far upstream and downstream of the gene were engineered to contain a lacZ reporter cassette and tested in transgenic mice. Each BAC clone directs a distinct subset of normal Bmp2 expression patterns, suggesting a modular arrangement of distant Bmp2 regulatory elements. Strikingly, regulatory sequences required for Bmp2 expression in differentiating osteoblasts, as well as tooth buds, hair placodes, kidney, and other tissues, are located more than 53 kilobases 3' to the promoter. By testing BACs with engineered deletions across this distant 3' region, we parsed these regulatory elements into separate locations and more closely refined the location of the osteoblast progenitor element. Finally, a conserved osteoblast progenitor enhancer was identified within a 656-bp sequence located 156.3 kilobases 3' from the promoter. The identification of this enhancer should permit further investigation of upstream regulatory mechanisms that control Bmp2 transcription during osteoblast differentiation and are relevant to further studies of Bmp2 as a candidate risk factor gene for osteoporosis.
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Affiliation(s)
- Ronald L Chandler
- Department of Molecular Physiology and Biophysics, Center for Human Genetics Research, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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30
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Gebhard S, Hattori T, Bauer E, Bösl MR, Schlund B, Pöschl E, Adam N, de Crombrugghe B, von der Mark K. BAC constructs in transgenic reporter mouse lines control efficient and specific LacZ expression in hypertrophic chondrocytes under the complete Col10a1 promoter. Histochem Cell Biol 2007; 127:183-94. [PMID: 17051351 PMCID: PMC1779629 DOI: 10.1007/s00418-006-0236-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2006] [Indexed: 02/06/2023]
Abstract
During endochondral ossification hypertrophic chondrocytes in the growth plate of fetal long bones, ribs and vertebrae play a key role in preparing growth plate cartilage for replacement by bone. In order to establish a reporter gene mouse to facilitate functional analysis of genes expressed in hypertrophic chondrocytes in this process, Col10a1- BAC reporter gene mouse lines were established expressing LacZ specifically in hypertrophic cartilage under the control of the complete Col10a1 gene. For this purpose, a bacterial artificial chromosome (BAC RP23-192A7) containing the entire murine Col10a1 gene together with 200 kb flanking sequences was modified by inserting a LacZ-Neo cassette into the second exon of Col10a1 by homologous recombination in E. coli. Transgenic mice containing between one and seven transgene copies were generated by injection of the purified BAC-Col10a1- lLacZ DNA. X-gal staining of newborns and embryos revealed strong and robust LacZ activity exclusively in hypertrophic cartilage of the fetal and neonatal skeleton of the transgenic offspring. This indicates that expression of the reporter gene in its proper genomic context in the BAC Col10a1 environment is independent of the integration site and reflects authentic Col10a1 expression in vivo. The Col10a1 specific BAC recombination vector described here will enable the specific analysis of effector gene functions in hypertrophic cartilage during skeletal development, endochondral ossification, and fracture callus healing.
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Affiliation(s)
- Sonja Gebhard
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
| | - Takako Hattori
- Department of Molecular Genetics, MD Anderson Cancer Center, University of Texas, Houston, TX 77030 USA
- Department of Biochemistry and Molecular Dentistry, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, 700-5525 Japan
| | - Eva Bauer
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
| | | | - Britta Schlund
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
| | - Ernst Pöschl
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
- University of East Anglia, School of Biological Sciences, Norwich, NR4 7TJ UK
| | - Nadia Adam
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
| | - Benoit de Crombrugghe
- Department of Molecular Genetics, MD Anderson Cancer Center, University of Texas, Houston, TX 77030 USA
| | - Klaus von der Mark
- Department of Experimental Medicine I, Nikolaus-Fiebiger Center of Molecular Medicine, University of Erlangen-Nuremberg, Glueckstr.6, 91054 Erlangen, Germany
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31
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Wilkins JM, Southam L, Price AJ, Mustafa Z, Carr A, Loughlin J. Extreme context specificity in differential allelic expression. Hum Mol Genet 2007; 16:537-46. [PMID: 17220169 DOI: 10.1093/hmg/ddl488] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Variability in cis-regulation of gene expression has been implicated in the phenotypic manifestation of complex traits including common, multifactorial diseases. The differential expression of alleles due to polymorphism in cis-regulatory elements is common in the human genome, but there is a paucity of information about the context specificity of these control elements. In this study, we examined the differential allelic expression (DAE) of BMP5 in human mesenchymal tissues obtained from 16 donors undergoing joint replacement for treatment of osteoarthritis. We observed significant differences in BMP5 allelic output, with allelic ratios greater than 4:1 (P < 10(-20)) in the tissues of some donors. We also discovered a significant variability in allelic expression within the different tissues of donors. For 12 of our donors, we examined the allelic expression of BMP5 in two different regions of cartilage: cartilage adjacent to the site of the osteoarthritic lesion and cartilage distal from the lesion. Five of these 12 donors demonstrated highly significant differences (P < or = 10(-8)) in allelic expression between the different regions of their cartilage. Using DAE as a phenotype, we attempted to map tissue-specific cis-regulatory polymorphisms, and we identified a single nucleotide polymorphism located downstream of BMP5, which was significantly associated with DAE in some but not all of the examined tissues. These findings suggest that allelic expression can be highly context specific and that when interrogating the cis-regulatory control of a particular gene, one cannot necessarily assume that allelic expression is conserved across different tissues or even across different regions of the same tissue.
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Affiliation(s)
- James M Wilkins
- University of Oxford, Institute of Musculoskeletal Sciences, Botnar Research Centre, Nuffield Orthopaedic Centre, Oxford OX3 7LD, UK.
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32
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Islam ME, Kikuta H, Inoue F, Kanai M, Kawakami A, Parvin MS, Takeda H, Yamasu K. Three enhancer regions regulate gbx2 gene expression in the isthmic region during zebrafish development. Mech Dev 2006; 123:907-24. [PMID: 17067785 DOI: 10.1016/j.mod.2006.08.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2006] [Revised: 08/16/2006] [Accepted: 08/24/2006] [Indexed: 10/24/2022]
Abstract
In vertebrate embryos, positioning of the boundary between the midbrain and hindbrain (MHB) and subsequent isthmus formation are dependent upon the interaction between the Otx2 and Gbx genes. In zebrafish, sequential expression of gbx1 and gbx2 in the anterior hindbrain contributes to this process, whereas in mouse embryos, a single Gbx gene (Gbx2) is responsible for MHB development. In the present study, to investigate the regulatory mechanism of gbx2 in the MHB/isthmic region of zebrafish embryos, we cloned the gene and showed that its organization is conserved among different vertebrates. Promoter analyses revealed three enhancers that direct reporter gene expression after the end of epiboly in the anterior-most hindbrain, which is a feature of the zebrafish gbx2 gene. One of the enhancers is located upstream of gbx2 (AMH1), while the other two enhancers are located downstream of gbx2 (AMH2 and AMH3). Detailed analysis of the AMH1 enhancer showed that it directs expression in the rhombomere 1 (r1) region and the dorsal thalamus, as has been shown for gbx2, whereas no expression was induced by the AMH1 enhancer in other embryonic regions in which gbx2 is expressed. The AMH1 enhancer is composed of multiple regulatory subregions that share the same spatial specificity. The most active of the regulatory subregions is a 291-bp region that contains at least two Pax2-binding sites, both of which are necessary for the function of the main component (PB1-A region) of the AMH1 enhancer. In accordance with these results, enhancer activity in the PB1-A region, as well as gbx2 expression in r1, was missing in no isthmus mutant embryos that lacked functional pax2a. In addition, we identified an upstream conserved sequence of 227bp that suppresses the enhancer activity of AMH1. Taken together, these findings suggest that gbx2 expression during the somitogenesis stage in zebrafish is regulated by a complex mechanism involving Pax2 as well as activators and suppressors in the regions flanking the gene.
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Affiliation(s)
- Md Ekramul Islam
- Division of Life Science, Graduate School of Science and Engineering, Saitama University, Shimo-Okubo, Sakura-ku, Saitama City, Saitama 338-8570, Japan
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33
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Amemiya CT, Gomez-Chiarri M. Comparative genomics in vertebrate evolution and development. ACTA ACUST UNITED AC 2006; 305:672-82. [PMID: 16902957 DOI: 10.1002/jez.a.308] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The vast quantities of publicly available DNA sequencing data and genome resources are enabling biologists to investigate age-old problems in biology that were not addressable previously. In this review, we discuss how comparative genomics is practiced and how the data can be used to make biological inferences with respect to vertebrate evolution and development. Examples are taken from the well-known HOX clusters, which are always a high-priority target for genomic analyses due to their inferred role in the evolution of metazoans. In addition, we briefly discuss the application of genomic approaches to problems in comparative endocrinology.
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Affiliation(s)
- Chris T Amemiya
- Molecular Genetics Program, Benaroya Research Institute at Virginia Mason, Seattle, Washington 98101, USA.
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Abstract
The threespine stickleback (Gasterosteus aculeatus) is rapidly emerging as a new model genetic system to study questions at the interface of evolution and development. The relatively rapid and recent diversification of this small teleost fish, combined with the development of genetic and genomic tools for this fish, provides an unprecedented opportunity to identify the genetic and molecular basis of morphological variation in natural populations of vertebrates. Recently, the genes underlying two different adaptive morphological traits in stickleback have been identified. This work has provided answers to four longstanding questions in the field of evolution and development: (1) How many genes underlie morphological variation in natural populations? (2) What are the genes that underlie morphological variation in natural populations? (3) Do coding or regulatory mutations underlie morphological evolution? (4) What is the molecular and genetic basis of parallel morphological evolution? Because stickleback populations also display natural variation in morphology, life history, physiology, and behavior, extending the approaches used to identify the genetic basis of morphological variation in sticklebacks to other phenotypes is sure to yield further important insights into the genetic and developmental basis of diversity in natural populations.
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Affiliation(s)
- Catherine L Peichel
- Division of Human Biology, Fred Hutchinson Cancer Research Center, Seattle, WA 98109, USA.
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Beermann F, Kaloulis K, Hofmann D, Murisier F, Bucher P, Trumpp A. Identification of evolutionarily conserved regulatory elements in the mouse Fgf8 locus. Genesis 2006; 44:1-6. [PMID: 16397882 DOI: 10.1002/gene.20177] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The secreted signaling molecule fibroblast growth factor 8 (Fgf8) is an essential component of certain embryonic signaling centers including the mid-hindbrain (isthmic) organizer, the first branchial arch (BA1), and the apical ectodermal ridge (AER). In these signaling centers Fgf8 transcripts are expressed in a dynamic and transient fashion, but the mechanism by which this highly specific expression pattern is established remains largely unknown. We used DNA sequence comparisons coupled to transgenic approaches to obtain insight into the structure and function of regulatory elements in the Fgf8 locus. First, a bacterial artificial chromosome (BAC) containing the mouse Fgf8 gene partially rescues the embryonic lethality of Fgf8-deficient mice and controls Fgf8-specific gene expression of a coinjected lacZ reporter transgene. Second, sequence comparison of vertebrate Fgf8 loci revealed evolutionarily highly conserved noncoding sequences that were unexpectedly located mainly 3' of the Fgf8 coding region. Third, in transgenic mice some of these elements were sufficient to target expression to the AER, tail bud, and brain, including the isthmic organizer, indicating that they may represent Fgf8 cis-acting elements. Collectively, these data identify novel regulatory elements of the Fgf8 gene sufficient to drive expression to regions of known Fgf8 activity.
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Affiliation(s)
- Friedrich Beermann
- Swiss Institute for Experimental Cancer Research (ISREC), Epalinges, Switzerland
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36
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Pimenta AF, Levitt P. Applications of gene targeting technology to mental retardation and developmental disability research. ACTA ACUST UNITED AC 2006; 11:295-302. [PMID: 16240411 DOI: 10.1002/mrdd.20084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
The human and mouse genome projects elucidated the sequence and position map of innumerous genes expressed in the central nervous system (CNS), advancing our ability to manipulate these sequences and create models to investigate regulation of gene expression and function. In this article, we reviewed gene targeting methodologies with emphasis on applications to CNS development and neurodevelopmental disorders.
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Affiliation(s)
- Aurea F Pimenta
- Vanderbilt Kennedy Center for Research on Human Development, Vanderbilt University, Nashville, Tennessee 37203, USA
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37
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Abstract
Transforming growth factor-beta (TGF-beta) superfamily members play diverse roles in all aspects of cartilage development and maintenance. It is well established that TGF-betas and bone morphogenetic proteins (BMPs) play distinct roles in the growth plate. This chapter discusses key experiments and experimental approaches that have revealed these roles, and progress toward the identification of previously unsuspected roles. Current understanding of the mechanisms by which different TGF-beta and BMP pathways exert their functions is discussed. Finally attempts to utilize this information to promote cartilage regeneration, and important issues for future research, are outlined.
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Affiliation(s)
- Robert Pogue
- Department of Orthopaedic Surgery, University of California Los Angeles, California 90095, USA
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38
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Abstract
Among more than 120 genes that are now known to regulate mammalian pigmentation, one of the key genes is MC1R, which encodes the melanocortin 1 receptor, a seven transmembrane G protein-coupled receptor expressed on the surface of melanocytes. Since the monoexonic sequence of the gene was cloned and characterized more than a decade ago, tremendous efforts have been dedicated to the extensive genotyping of mostly red-haired populations all around the world, thus providing allelic variants that may or may not account for melanoma susceptibility in the presence or absence of ultraviolet (UV) exposure. Soluble factors, such as proopiomelanocortin (POMC) derivatives, agouti signal protein (ASP) and others, regulate MC1R expression, leading to improved photoprotection via increased eumelanin synthesis or in contrast, inducing the switch to pheomelanin. However, there is an obvious lack of knowledge regarding the numerous and complex regulatory mechanisms that govern the expression of MC1R at the intra-cellular level, from gene transcription in response to an external stimulus to the expression of the mature receptor on the melanocyte surface.
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Affiliation(s)
- Francois Rouzaud
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Building 37, Room 2132, Bethesda, MD 20892, USA
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39
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Khandekar M, Suzuki N, Lewton J, Yamamoto M, Engel JD. Multiple, distant Gata2 enhancers specify temporally and tissue-specific patterning in the developing urogenital system. Mol Cell Biol 2005; 24:10263-76. [PMID: 15542836 PMCID: PMC529040 DOI: 10.1128/mcb.24.23.10263-10276.2004] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Transcription factor GATA-2 is expressed in a complex temporally and tissue-specific pattern within the developing embryo. Loss-of-function studies in the mouse showed that GATA-2 activity is first required during very early hematopoiesis. We subsequently showed that a 271-kbp yeast artificial chromosome (YAC) transgene could fully complement the loss of Gata2 hematopoietic function but that these YAC-rescued Gata2 null mutant mice die perinatally due to defective urogenital development. The rescuing YAC did not display appropriate urogenital expression of Gata2, implying the existence of a urogenital-specific enhancer(s) lying outside the boundaries of this transgene. Here we outline a coupled general strategy for regulatory sequence discovery, linking bioinformatics to functional genomics based on the bacterial artificial chromosome (BAC) libraries used to generate the mouse genome sequence. Exploiting this strategy, we screened >1 Mbp of genomic DNA surrounding Gata2 for urogenital enhancer activity. We found that the spatially and tissue-specific functions for Gata2 in the developing urogenital system are conferred by at least three separate regionally and temporally specific urogenital enhancer elements, two of which reside far 3' to the Gata2 structural gene. Including the additional enhancers that were discovered using this strategy (called BAC trap) extends the functional realm of the Gata2 locus to greater than 1 Mbp.
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MESH Headings
- Animals
- Arabinose/metabolism
- Body Patterning
- Chromosomes, Artificial, Bacterial
- Chromosomes, Artificial, Yeast
- Computational Biology
- DNA Nucleotidyltransferases/metabolism
- DNA-Binding Proteins/genetics
- Enhancer Elements, Genetic
- Escherichia coli/metabolism
- GATA2 Transcription Factor
- Gene Deletion
- Gene Library
- Genes, Reporter
- Genome
- Immunohistochemistry
- Lac Operon
- Mice
- Models, Biological
- Models, Genetic
- Mutation
- Plasmids/metabolism
- Promoter Regions, Genetic
- Recombination, Genetic
- Time Factors
- Transcription Factors/genetics
- Transcription, Genetic
- Transgenes
- Urogenital System/embryology
- Urogenital System/physiology
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Affiliation(s)
- Melin Khandekar
- Department of Cell and Developmental Biology, 4643 Med. Sci. II, 1335 Catherine St., Ann Arbor, MI 48109, USA
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40
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Kleinjan DA, van Heyningen V. Long-range control of gene expression: emerging mechanisms and disruption in disease. Am J Hum Genet 2005; 76:8-32. [PMID: 15549674 PMCID: PMC1196435 DOI: 10.1086/426833] [Citation(s) in RCA: 645] [Impact Index Per Article: 33.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2004] [Accepted: 10/08/2004] [Indexed: 02/04/2023] Open
Abstract
Transcriptional control is a major mechanism for regulating gene expression. The complex machinery required to effect this control is still emerging from functional and evolutionary analysis of genomic architecture. In addition to the promoter, many other regulatory elements are required for spatiotemporally and quantitatively correct gene expression. Enhancer and repressor elements may reside in introns or up- and downstream of the transcription unit. For some genes with highly complex expression patterns--often those that function as key developmental control genes--the cis-regulatory domain can extend long distances outside the transcription unit. Some of the earliest hints of this came from disease-associated chromosomal breaks positioned well outside the relevant gene. With the availability of wide-ranging genome sequence comparisons, strong conservation of many noncoding regions became obvious. Functional studies have shown many of these conserved sites to be transcriptional regulatory elements that sometimes reside inside unrelated neighboring genes. Such sequence-conserved elements generally harbor sites for tissue-specific DNA-binding proteins. Developmentally variable chromatin conformation can control protein access to these sites and can regulate transcription. Disruption of these finely tuned mechanisms can cause disease. Some regulatory element mutations will be associated with phenotypes distinct from any identified for coding-region mutations.
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Affiliation(s)
- Dirk A Kleinjan
- MRC Human Genetics Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, Scotland, United Kingdom
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41
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Mortlock DP, Portnoy ME, Chandler RL, Green ED. Comparative sequence analysis of the Gdf6 locus reveals a duplicon-mediated chromosomal rearrangement in rodents and rapidly diverging coding and regulatory sequences. Genomics 2004; 84:814-23. [DOI: 10.1016/j.ygeno.2004.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2004] [Accepted: 07/18/2004] [Indexed: 11/24/2022]
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42
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Tanaka S, Antoniv TT, Liu K, Wang L, Wells DJ, Ramirez F, Bou-Gharios G. Cooperativity between far upstream enhancer and proximal promoter elements of the human {alpha}2(I) collagen (COL1A2) gene instructs tissue specificity in transgenic mice. J Biol Chem 2004; 279:56024-31. [PMID: 15516691 DOI: 10.1074/jbc.m411406200] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Interaction between the proximal (-378) promoter and the far upstream (-20 kb) enhancer is essential for tissue-specific expression of the human alpha2(I) collagen gene (COL1A2) in transgenic mice. Previous in vitro studies have shown that three Sp1 binding sites (around -300) are part of a cytokine-responsive element and that two TC-rich boxes (around -160 and -125) and a CBF/NFY consensus sequence (around -80) confer optimal promoter activity by interacting among themselves and with the upstream Sp1 sites. Here we report that mutations of the Sp1 binding sites, TC-rich boxes or CBF/NFY consensus sequence lead to reduced transgene activity, thus underscoring the functional interdependence of the proximal promoter elements. Loss of the Sp1 binding sites was associated with loss of transgene expression in osteoblasts, whereas elimination of the CBF/NFY binding site (alone or in combination with the TC-rich boxes) was correlated with a lack of activity in the ventral fascia and head dermis and musculature. Additionally, transgene expression in skin fascia fibroblasts depended on the integrity of the Sp1 binding sites and TC-rich boxes, and on their physical configuration. Evidence is also presented suggesting cooperativity between cis-acting elements of the far upstream enhancer and proximal promoter in assembling tissue-specific protein complexes. This study thus reiterates the complex and highly combinatorial nature of the regulatory network governing COL1A2 transcription in vivo.
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Affiliation(s)
- Shizuko Tanaka
- Laboratory of Genetics and Organogenesis, Research Division of the Hospital for Special Surgery, Weill Medical College of Cornell University, 535 East 70th Street, New York, NY 10021, USA
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43
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Sebald W, Nickel J, Zhang JL, Mueller TD. Molecular recognition in bone morphogenetic protein (BMP)/receptor interaction. Biol Chem 2004; 385:697-710. [PMID: 15449706 DOI: 10.1515/bc.2004.086] [Citation(s) in RCA: 120] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractBone morphogenetic proteins (BMPs) and other members of the TGF-β superfamily are secreted signalling proteins determining the development, maintenance and regeneration of tissues and organs. These dimeric proteins bind, via multiple epitopes, two types of signalling receptor chains and numerous extracellular modulator proteins that stringently control their activity. Crystal structures of free ligands and of complexes with type I and type II receptor extracellular domains and with the modulator protein Noggin reveal structural epitopes that determine the affinity and specificity of the interactions. Modelling of a ternary complex BMP/(BMPR-IAEC)2/(ActR-IIEC)2suggests a mechanism of receptor activation that does not rely on direct contacts between extracellular domains of the receptors. Mutational and interaction analyses indicate that the large hydrophobic core of the interface of BMP-2 (wrist epitope) with the type I receptor does not provide a hydrophobic hot spot for binding. Instead, main chain amide and carbonyl groups that are completely buried in the contact region represent major binding determinants. The affinity between ligand and receptor chains is probably strongly increased by two-fold interactions of the dimeric ligand and receptor chains that exist as homodimers in the membrane (avidity effects). BMP muteins with disrupted epitopes for receptor chains or modulator proteins provide clues for drug design and development.
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Affiliation(s)
- Walter Sebald
- Physiologische Chemie II, Theodor-Boveri-Institut für Biowissenschaften (Biozentrum) der Universität Würzburg, D-97074 Würzburg, Germany.
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44
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Miyake T, Amemiya CT. BAC libraries and comparative genomics of aquatic chordate species. Comp Biochem Physiol C Toxicol Pharmacol 2004; 138:233-44. [PMID: 15533781 DOI: 10.1016/j.cca.2004.07.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/25/2004] [Revised: 07/09/2004] [Accepted: 07/14/2004] [Indexed: 11/26/2022]
Abstract
The bacterial artificial chromosome (BAC) system is useful for creating a representation of the genomes of target species. The system is advantageous in that it can accommodate exogenous inserts that are very large (>100 kilobases, kb), thereby allowing entire eukaryotic genes (including flanking regulatory regions) to be encompassed in a single clone. The interest in BACs has recently been spawned by vast improvements in high throughput genomic sequencing such that comparisons of orthologous regions from different genomes (comparative genomics) are being routinely investigated, and comprise a significant component, of all major sequencing centers. In this review, we discuss the general principles of BAC cloning, the resources that are currently available, and some of the applications of the technology. It is not intended to be an exhaustive treatise; rather our goal is to provide a primer of the BAC technology in order to make readers aware of these resources and how they may utilize them in their own research programs.
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Affiliation(s)
- Tsutomu Miyake
- Molecular Genetics Department, Benaroya Research Institute at Virginia Mason, 1201 Ninth Avenue, Seattle, WA 98101, USA.
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45
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Abstract
Santa Fe - with its museums and galleries full of art and crafts inspired by natural forms - was the perfect setting for a Keystone conference on vertebrate organogenesis in February 2004. Organized by Gail Martin and Cliff Tabin, the conference sessions were loosely subdivided into anatomical systems - 'skin, hair, teeth', 'pancreas, liver, gut', 'skeleton', and so on. However, from the outset, common themes emerged that transcended particular organ systems and generated a sense of unity and excitement among the participants.
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Affiliation(s)
- Brigid Hogan
- Department of Cell Biology, PO Box 3709, Duke University Medical Center, Durham, NC 27710, USA.
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46
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Karatsoreos IN, Yan L, LeSauter J, Silver R. Phenotype matters: identification of light-responsive cells in the mouse suprachiasmatic nucleus. J Neurosci 2004; 24:68-75. [PMID: 14715939 PMCID: PMC3271855 DOI: 10.1523/jneurosci.1666-03.2004] [Citation(s) in RCA: 105] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The suprachiasmatic nucleus (SCN) of the hypothalamus is the neural locus of the circadian clock. To explore the organization of the SCN, two strains of transgenic mice, each bearing a jellyfish green fluorescent protein (GFP) reporter, were used. In one, GFP was driven by the promoter region of the mouse Period1 gene (mPer1) (Per1::GFP mouse), whereas in the other, GFP was inserted in the promoter region of calbindin-D(28K)-bacterial artificial chromosome (CalB::GFP mouse). In the latter mouse, GFP-containing SCN cells are immunopositive for gastrin-releasing peptide. In both mouse lines, light-induced Per1 mRNA and Fos are localized to the SCN subregion containing gastrin-releasing peptide. Double-label immunohistochemistry reveals that most gastrin-releasing peptide cells (approximately 70%) contain Fos after a brief light pulse. To determine the properties of SCN cells in this light-responsive region, we examined the expression of rhythmic Period genes and proteins. Gastrin-releasing peptide-containing cells do not express detectable rhythms in these key components of the molecular circadian clock. The results support the view that the mammalian SCN is composed of functionally distinct cell groups, of which some are light induced and others are rhythmic with respect to clock gene expression. Furthermore, the findings suggest that gastrin-releasing peptide is a potential mediator of intercellular communication between light-induced and oscillator cells within the SCN.
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Affiliation(s)
- Ilia N Karatsoreos
- Department of Psychology, Columbia University, New York, New York 10027, USA
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47
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Mortlock DP, Guenther C, Kingsley DM. A general approach for identifying distant regulatory elements applied to the Gdf6 gene. Genome Res 2003; 13:2069-81. [PMID: 12915490 PMCID: PMC403689 DOI: 10.1101/gr.1306003] [Citation(s) in RCA: 78] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Regulatory sequences in higher genomes can map large distances from gene coding regions, and cannot yet be identified by simple inspection of primary DNA sequence information. Here we describe an efficient method of surveying large genomic regions for gene regulatory information, and subdividing complex sets of distant regulatory elements into smaller intervals for detailed study. The mouse Gdf6 gene is expressed in a number of distinct embryonic locations that are involved in the patterning of skeletal and soft tissues. To identify sequences responsible for Gdf6 regulation, we first isolated a series of overlapping bacterial artificial chromosomes (BACs) that extend varying distances upstream and downstream of the gene. A LacZ reporter cassette was integrated into the Gdf6 transcription unit of each BAC using homologous recombination in bacteria. Each modified BAC was injected into fertilized mouse eggs, and founder transgenic embryos were analyzed for LacZ expression mid-gestation. The overlapping segments defined by the BAC clones revealed five separate regulatory regions that drive LacZ expression in 11 distinct anatomical locations. To further localize sequences that control expression in developing skeletal joints, we created a series of BAC constructs with precise deletions across a putative joint-control region. This approach further narrowed the critical control region to an area containing several stretches of sequence that are highly conserved between mice and humans. A distant 2.9-kilobase fragment containing the highly conserved regions is able to direct very specific expression of a minimal promoter/LacZ reporter in proximal limb joints. These results demonstrate that even distant, complex regulatory sequences can be identified using a combination of BAC scanning, BAC deletion, and comparative sequencing approaches.
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Affiliation(s)
- Douglas P Mortlock
- Department of Developmental Biology and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California 94305-5329, USA
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48
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Zhou J, Zhao LQ, Xiong MM, Wang XQ, Yang GR, Qiu ZL, Wu M, Liu ZH. Gene expression profiles at different stages of human esophageal squamous cell carcinoma. World J Gastroenterol 2003; 9:9-15. [PMID: 12508342 PMCID: PMC4728257 DOI: 10.3748/wjg.v9.i1.9] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To characterize the gene expression profiles in different stages of carcinogenesis of esophageal epithelium.
METHODS: A microarray containing 588 cancer related genes was employed to study the gene expression profile at different stages of esophageal squamous cell carcinoma including basal cell hyperplasia, high-grade dysplasia, carcinoma in situ, early and late cancer. Principle component analysis was performed to search the genes which were important in carcinogenesis.
RESULTS: More than 100 genes were up or down regulated in esophageal epithelial cells during the stages of basal cell hyperplasia, high-grade dysplasia, carcinoma in situ, early and late cancer. Principle component analysis identified a set of genes which may play important roles in the tumor development. Comparison of expression profiles between these stages showed that some genes, such as P160ROCK, JNK2, were activated and may play an important role in early stages of carcinogenesis.
CONCLUSION: These findings provided an esophageal cancer-specific and stage-specific expression profiles, showing that complex alterations of gene expression underlie the development of malignant phenotype of esophageal cancer cells.
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Affiliation(s)
- Jin Zhou
- National Laboratory of Molecular Oncology, Cancer Institute, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing 100021, China
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49
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Feng JQ, Zhang J, Tan X, Lu Y, Guo D, Harris SE. Identification of cis-DNA regions controlling Bmp4 expression during tooth morphogenesis in vivo. J Dent Res 2002; 81:6-10. [PMID: 11820370 DOI: 10.1177/002203450208100103] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Epithelial-mesenchymal interactions are required for tooth formation. Bone morphogenetic protein 4 (Bmp4) is a crucial signaling molecule during this process. For better understanding of the role of the Bmp4 gene during tooth development, we studied the mechanisms that control its temporal and spatial expression during development. Using a transgenic approach, we determined that the domains which controlled Bmp4 expression in epithelium-derived ameloblasts were located in the region between 0.26 kb and 1.1 kb of the murine Bmp4 promoter. In contrast, the domains controlling Bmp4 expression in mesenchyme-derived odontoblasts and pulp cells existed in other regions of the Bmp4 gene. We have also demonstrated that the domains controlling Bmp4 expression in primordial tooth cells differ from those controlling Bmp4 expression in mature tooth tissues. The determination of unique domains by controlling the expression of the Bmp4 gene suggests that different transcriptional factors regulate the Bmp4 level at different stages during tooth morphogenesis.
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Affiliation(s)
- J Q Feng
- School of Dentistry, Dept. of Oral Biology, University of Missouri-Kansas City, 64108, USA.
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50
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Kohler S, Pradervand S, Verdumo C, Mérillat AM, Bens M, Vandewalle A, Beermann F, Hummler E. Analysis of the mouse Scnn1a promoter in cortical collecting duct cells and in transgenic mice. BIOCHIMICA ET BIOPHYSICA ACTA 2001; 1519:106-10. [PMID: 11406278 DOI: 10.1016/s0167-4781(01)00228-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
We have isolated and characterised the promoter of the mouse Scnn1a (alpha ENaC) gene. Using transient transfections of serial deletion mutants into Scnn1a-expressing cells, we demonstrate that 1.56 kb of 5' upstream sequence is required for cell-specific expression and corticosteroid-mediated regulation. These 5' sequences are not sufficient to drive expression of a lacZ reporter gene or a rat Scnn1a cDNA in transgenic mice, where they failed to rescue Scnn1a deficiency.
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Affiliation(s)
- S Kohler
- Institute of Pharmacology and Toxicology, University of Lausanne, Switzerland
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