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Akhlaghpour M, Haley E, Parnell L, Luke N, Mathur M, Festa RA, Percaccio M, Magallon J, Remedios-Chan M, Rosas A, Wang J, Jiang Y, Anderson L, Baunoch D. Urine biomarkers individually and as a consensus model show high sensitivity and specificity for detecting UTIs. BMC Infect Dis 2024; 24:153. [PMID: 38297221 PMCID: PMC10829179 DOI: 10.1186/s12879-024-09044-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 01/22/2024] [Indexed: 02/02/2024] Open
Abstract
BACKGROUND Current diagnoses of urinary tract infection (UTI) by standard urine culture (SUC) has significant limitations in sensitivity, especially for fastidious organisms, and the ability to identify organisms in polymicrobial infections. The significant rate of both SUC "negative" or "mixed flora/contamination" results in UTI cases and the high prevalence of asymptomatic bacteriuria indicate the need for an accurate diagnostic test to help identify true UTI cases. This study aimed to determine if infection-associated urinary biomarkers can differentiate definitive UTI cases from non-UTI controls. METHODS Midstream clean-catch voided urine samples were collected from asymptomatic volunteers and symptomatic subjects ≥ 60 years old diagnosed with a UTI in a urology specialty setting. Microbial identification and density were assessed using a multiplex PCR/pooled antibiotic susceptibility test (M-PCR/P-AST) and SUC. Three biomarkers [neutrophil gelatinase-associated lipocalin (NGAL), and Interleukins 8 and 1β (IL-8, and IL-1β)] were also measured via enzyme-linked immunosorbent assay (ELISA). Definitive UTI cases were defined as symptomatic subjects with a UTI diagnosis and positive microorganism detection by SUC and M-PCR, while definitive non-UTI cases were defined as asymptomatic volunteers. RESULTS We observed a strong positive correlation (R2 > 0.90; p < 0.0001) between microbial density and the biomarkers NGAL, IL-8, and IL-1β for symptomatic subjects. Biomarker consensus criteria of two or more positive biomarkers had sensitivity 84.0%, specificity 91.2%, positive predictive value 93.7%, negative predictive value 78.8%, accuracy 86.9%, positive likelihood ratio of 9.58, and negative likelihood ratio of 0.17 in differentiating definitive UTI from non-UTI cases, regardless of non-zero microbial density. NGAL, IL-8, and IL-1β showed a significant elevation in symptomatic cases with positive microbe identification compared to asymptomatic cases with or without microbe identification. Biomarker consensus exhibited high accuracy in distinguishing UTI from non-UTI cases. CONCLUSION We demonstrated that positive infection-associated urinary biomarkers NGAL, IL-8, and IL-1β, in symptomatic subjects with positive SUC and/or M-PCR results was associated with definitive UTI cases. A consensus criterion with ≥ 2 of the biomarkers meeting the positivity thresholds showed a good balance of sensitivity (84.0%), specificity (91.2%), and accuracy (86.9%). Therefore, this biomarker consensus is an excellent supportive diagnostic tool for resolving the presence of active UTI, particularly if SUC and M-PCR results disagree.
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Affiliation(s)
- Marzieh Akhlaghpour
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Emery Haley
- Department of Clinical Research, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Laura Parnell
- Department of Scientific Writing, Precision Consulting, 6522 Harbor Mist, Missouri City, TX, 77459, USA
| | - Natalie Luke
- Department of Clinical Research, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Mohit Mathur
- Department of Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Richard A Festa
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Michael Percaccio
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Jesus Magallon
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Mariana Remedios-Chan
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Alain Rosas
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA
| | - Jimin Wang
- Department of Statistical Analysis, Stat4Ward, 2 Edgemoor Lane, Pittsburgh, PA, 15238, USA
| | - Yan Jiang
- Department of Statistical Analysis, Stat4Ward, 2 Edgemoor Lane, Pittsburgh, PA, 15238, USA
| | - Lori Anderson
- Department of Writing, L. Anderson Diagnostic Market Access Consulting, 2755 Eagle Street, San Diego, CA, 92103, USA
| | - David Baunoch
- Department of Research and Development, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA, 92618, USA.
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Festa RA, Luke N, Mathur M, Parnell L, Wang D, Zhao X, Magallon J, Remedios-Chan M, Nguyen J, Cho T, Ngo A, Murphy M, Baunoch D. A test combining multiplex-PCR with pooled antibiotic susceptibility testing has high correlation with expanded urine culture for detection of live bacteria in urine samples of suspected UTI patients. Diagn Microbiol Infect Dis 2023; 107:116015. [PMID: 37499607 DOI: 10.1016/j.diagmicrobio.2023.116015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/25/2023] [Accepted: 06/30/2023] [Indexed: 07/29/2023]
Abstract
We evaluated whether multiplex polymerase chain reaction (M-PCR) detects viable micro-organisms by comparing micro-organism identification with standard urine culture (SUC) and expanded quantitative urine culture (EQUC). Of the 395 organisms detected by M-PCR, EQUC detected 89.1% (p = 0.10), whereas SUC detected 27.3% (p < 0.0001 vs. M-PCR and p < 0.0001 vs EQUC). M-PCR identified 260 nonfastidious bacteria, EQUC detected 96.5% (p = 0.68), whereas SUC detected 41.5% (p < 0.0001). Common nonfastidious bacteria missed by SUC included Escherichia coli (72.5% detected), Klebsiella pneumoniae (66.7% detected), Enterococcus faecalis (34.6% detected) and Enterococcus faecium (0% detected). M-PCR identified 135 fastidious bacteria and EQUC 101 (74.8%, p = 0.01), whereas SUC failed to detect any (0%, p < 0.0001). Clinical samples evaluated using EQUC and M-PCR yielded very similar findings, indicating that most microbes identified by M-PCR represented viable organisms, and validating M-PCR as a diagnostic tool for UTIs.
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Affiliation(s)
- Richard A Festa
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Natalie Luke
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Mohit Mathur
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Laura Parnell
- Department of Scientific Writing, Precision Consulting, 6522 Harbor Mist, Missouri City, TX 77459, USA
| | - Dakun Wang
- Department of Statistical Analysis and Writing, Stat4Ward, 2 Edgemoor Lane, Pittsburgh, PA 15238, USA
| | - Xinhua Zhao
- Department of Statistical Analysis and Writing, Stat4Ward, 2 Edgemoor Lane, Pittsburgh, PA 15238, USA
| | - Jesus Magallon
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Marina Remedios-Chan
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Jasmine Nguyen
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Tim Cho
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Annie Ngo
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - Max Murphy
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA
| | - David Baunoch
- Department of Research and Development & Medical Affairs, Pathnostics, 15545 Sand Canyon Suite 100, Irvine, CA 92618, USA.
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Festa RA, Opel M, Mathur M, Luke N, Parnell LKS, Wang D, Zhao X, Magallon J, Percaccio M, Baunoch D. Quantitative multiplex polymerase chain reaction in copies ml-1 linearly correlates with standard urine culture in colonies ml-1 for urinary tract infection (UTI) pathogens. Lett Appl Microbiol 2023; 76:ovad085. [PMID: 37500537 DOI: 10.1093/lambio/ovad085] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Revised: 06/28/2023] [Accepted: 07/26/2023] [Indexed: 07/29/2023]
Abstract
Standard urine culture (SUC) is the current standard method for confirmation of a urinary tract infection (UTI). SUC identifies microorganisms in urine samples and semi-quantifies these as colony-forming units (CFUs) ml-1. In contrast, quantitative multiplex polymerase chain reaction (q-MPCR) is a culture-independent assay in which the microbes are quantified by targeting genomic sequences and reported as cells ml-1, calculated from copies ml-1. Using serial dilutions within the 104-105 cells ml-1 range, the usual reporting range of SUC, this study compared the quantification results based on SUC and q-MPCR for four uropathogens with the control hemocytometer counts. The results revealed a linear relationship and a 1:1 correlation between the q-MPCR and SUC results. Additional q-MPCR quantification of 36 uropathogenic non-fastidious and fastidious bacteria and yeast indicated a reproducible linear correlation in a 1:1 manner with the control counts over a range of cell densities (103-106 cells ml-1). The results confirm that the quantifications by q-MPCR in cells ml-1 and by SUC in CFUs ml-1 are comparable and answer to the lingering question of how the results of these two methods correlate. Moreover, q-MPCR provided accurate quantification of various microorganisms over wider cell density ranges without the time required for microbial growth.
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Affiliation(s)
| | - Mike Opel
- Pathnostics, Irvine, CA 92618, United States
| | | | | | | | - Dakun Wang
- Stat4ward, Pittsburgh, PA 15238, United States
| | - Xinhua Zhao
- Stat4ward, Pittsburgh, PA 15238, United States
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Rocha K, Magallon J, Reeves C, Phan K, Vu P, Oakley-Havens CL, Kwan S, Ramirez MS, LaVoi T, Donow H, Chapagain P, Santos R, Pinilla C, Giulianotti MA, Tolmasky ME. Inhibition of Aminoglycoside 6'- N-acetyltransferase Type Ib (AAC(6')-Ib): Structure-Activity Relationship of Substituted Pyrrolidine Pentamine Derivatives as Inhibitors. Biomedicines 2021; 9:biomedicines9091218. [PMID: 34572404 PMCID: PMC8471502 DOI: 10.3390/biomedicines9091218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 11/16/2022] Open
Abstract
The aminoglycoside 6'-N-acetyltransferase type Ib (AAC(6')-Ib) is a common cause of resistance to amikacin and other aminoglycosides in Gram-negatives. Utilization of mixture-based combinatorial libraries and application of the positional scanning strategy identified an inhibitor of AAC(6')-Ib. This inhibitor's chemical structure consists of a pyrrolidine pentamine scaffold substituted at four locations (R1, R3, R4, and R5). The substituents are two S-phenyl groups (R1 and R4), an S-hydroxymethyl group (R3), and a 3-phenylbutyl group (R5). Another location, R2, does not have a substitution, but it is named because its stereochemistry was modified in some compounds utilized in this study. Structure-activity relationship (SAR) analysis using derivatives with different functionalities, modified stereochemistry, and truncations was carried out by assessing the effect of the addition of each compound at 8 µM to 16 µg/mL amikacin-containing media and performing checkerboard assays varying the concentrations of the inhibitor analogs and the antibiotic. The results show that: (1) the aromatic functionalities at R1 and R4 are essential, but the stereochemistry is essential only at R4; (2) the stereochemical conformation at R2 is critical; (3) the hydroxyl moiety at R3 as well as stereoconformation are required for full inhibitory activity; (4) the phenyl functionality at R5 is not essential and can be replaced by aliphatic groups; (5) the location of the phenyl group on the butyl carbon chain at R5 is not essential; (6) the length of the aliphatic chain at R5 is not critical; and (7) all truncations of the scaffold resulted in inactive compounds. Molecular docking revealed that all compounds preferentially bind to the kanamycin C binding cavity, and binding affinity correlates with the experimental data for most of the compounds evaluated. The SAR results in this study will serve as the basis for the design of new analogs in an effort to improve their ability to induce phenotypic conversion to susceptibility in amikacin-resistant pathogens.
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Affiliation(s)
- Kenneth Rocha
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Jesus Magallon
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Craig Reeves
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Kimberly Phan
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Peter Vu
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Crista L. Oakley-Havens
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Stella Kwan
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Maria Soledad Ramirez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
| | - Travis LaVoi
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (T.L.); (H.D.); (C.P.); (M.A.G.)
| | - Haley Donow
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (T.L.); (H.D.); (C.P.); (M.A.G.)
| | - Prem Chapagain
- Department of Physics, Florida International University, Miami, FL 33199, USA;
- Biomolecular Sciences Institute, Florida International University, Miami, FL 33199, USA
| | - Radleigh Santos
- Department of Mathematics, Nova Southeastern University, Fort Lauderdale, FL 33314, USA;
| | - Clemencia Pinilla
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (T.L.); (H.D.); (C.P.); (M.A.G.)
| | - Marc A. Giulianotti
- Center for Translational Science, Florida International University, Port St. Lucie, FL 34987, USA; (T.L.); (H.D.); (C.P.); (M.A.G.)
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA 92831, USA; (K.R.); (J.M.); (C.R.); (K.P.); (P.V.); (C.L.O.-H.); (S.K.); (M.S.R.)
- Correspondence: ; Tel.: +1-657-278-5263
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Magallon J, Chiem K, Tran T, Ramirez MS, Jimenez V, Tolmasky ME. Restoration of susceptibility to amikacin by 8-hydroxyquinoline analogs complexed to zinc. PLoS One 2019; 14:e0217602. [PMID: 31141575 PMCID: PMC6541283 DOI: 10.1371/journal.pone.0217602] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 05/14/2019] [Indexed: 11/18/2022] Open
Abstract
Gram-negative pathogens resistant to amikacin and other aminoglycosides of clinical relevance usually harbor the 6’-N-acetyltransferase type Ib [AAC(6')-Ib], an enzyme that catalyzes inactivation of the antibiotic by acetylation using acetyl-CoA as donor substrate. Inhibition of the acetylating reaction could be a way to induce phenotypic conversion to susceptibility in these bacteria. We have previously observed that Zn2+ acts as an inhibitor of the enzymatic acetylation of aminoglycosides by AAC(6')-Ib, and in complex with ionophores it effectively reduced the levels of resistance in cellulo. We compared the activity of 8-hydroxyquinoline, three halogenated derivatives, and 5-[N-Methyl-N-Propargylaminomethyl]-8-Hydroxyquinoline in complex with Zn2+ to inhibit growth of amikacin-resistant Acinetobacter baumannii in the presence of the antibiotic. Two of the compounds, clioquinol (5-chloro-7-iodo-8-hydroxyquinoline) and 5,7-diiodo-8-hydroxyquinoline, showed robust inhibition of growth of the two A. baumannii clinical isolates that produce AAC(6')-Ib. However, none of the combinations had any activity on another amikacin-resistant A. baumannii strain that possesses a different, still unknown mechanism of resistance. Time-kill assays showed that the combination of clioquinol or 5,7-diiodo-8-hydroxyquinoline with Zn2+ and amikacin was bactericidal. Addition of 8-hydroxyquinoline, clioquinol, or 5,7-diiodo-8-hydroxyquinoline, alone or in combination with Zn2+, and amikacin to HEK293 cells did not result in significant toxicity. These results indicate that ionophores in complex with Zn2+ could be developed into potent adjuvants to be used in combination with aminoglycosides to treat Gram-negative pathogens in which resistance is mediated by AAC(6')-Ib and most probably other related aminoglycoside modifying enzymes.
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Affiliation(s)
- Jesus Magallon
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
| | - Kevin Chiem
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
| | - Tung Tran
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
| | - Maria S. Ramirez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
| | - Veronica Jimenez
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
| | - Marcelo E. Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, College of Natural Sciences and Mathematics, California State University Fullerton, Fullerton, CA, United States of America
- * E-mail:
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Chiem K, Hue F, Magallon J, Tolmasky ME. Inhibition of aminoglycoside 6'-N-acetyltransferase type Ib-mediated amikacin resistance by zinc complexed with clioquinol, an ionophore active against tumors and neurodegenerative diseases. Int J Antimicrob Agents 2017; 51:271-273. [PMID: 28782708 DOI: 10.1016/j.ijantimicag.2017.08.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Accepted: 08/01/2017] [Indexed: 10/19/2022]
Affiliation(s)
- Kevin Chiem
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA, USA
| | - Fong Hue
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA, USA
| | - Jesus Magallon
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA, USA
| | - Marcelo E Tolmasky
- Center for Applied Biotechnology Studies, Department of Biological Science, California State University Fullerton, Fullerton, CA, USA.
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Rodriguez-Esteban C, Tsukui T, Yonei S, Magallon J, Tamura K, Izpisua Belmonte JC. The T-box genes Tbx4 and Tbx5 regulate limb outgrowth and identity. Nature 1999; 398:814-8. [PMID: 10235264 DOI: 10.1038/19769] [Citation(s) in RCA: 234] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
During embryonic development, initially similar fields can develop into distinct structures, such as the vertebrate fore- and hindlimbs. Although considerable progress has been made in our understanding of the genetic control underlying the establishment of the different limb axes, the molecular cues that specify the differential development of the fore- and hindlimbs are unknown. Possible candidates for genes determining limb identity are Pitx1, a gene whose transcripts are detected in the early hind- but not forelimb bud, and two members of the T-box (Tbx) gene family, Tbx4 and Tbx5, which are specifically expressed in the hindlimb and forelimb buds, respectively. Here we show that Tbx4 and Tbx5 are essential regulators of limb outgrowth whose roles seem to be tightly linked to the activity of three signalling proteins that are required for limb outgrowth and patterning: fibroblast growth factor (FGF), bone morphogenetic protein (BMP) and Wnt. In addition, we provide evidence that Tbx4 and Tbx5 are involved in controlling limb identity. Our findings provide insight into how similar developmental fields can evolve into homologous but distinct structures.
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Affiliation(s)
- C Rodriguez-Esteban
- Gene Expression Laboratory, The Salk Institute, La Jolla, California 92037-1099, USA
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Schwabe JW, Rodriguez-Esteban C, De La Peña J, Tavares AT, Ng JK, Banayo EM, Foys B, Eshelman B, Magallon J, Tam R, Izpisúa-Belmonte JC. Outgrowth and patterning of the vertebrate limb. Cold Spring Harb Symp Quant Biol 1998; 62:431-5. [PMID: 9598378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- J W Schwabe
- Salk Institute, Gene Expression Laboratory, La Jolla, California 92037-1099, USA
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