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Bernadette Holdener, Ph.D.
Department of Biochemistry and Cell Biology
346 Centers for Molecular Medicine
Stony Brook University
Stony Brook, NY 11794-5215
Office telephone: 631-632-8292
Lab telephone: 631-632-8442
- Research Description
My laboratory is interested in understanding how defects in glycosylation lead to birth defects. In particular, our studies focus on understanding why it is so important to add an O-linked glucose-fucose disaccharide to the thrombospondin type I repeat (TSR) protein fold. The disaccharide is added to TSRs through the cooperative action of two enzymes, Protein O-fucosyltransferase 2 (POFUT2) and beta -3-glucosyltransferase (B3GLCT). POFUT2 recognizes its consensus sequence in properly folded TSRs and adds fucose. B3GLCT then adds glucose to form the unusual Glucose-beta1-3Fucose disaccharide. The POFUT2 consensus sequence is present in only 49 TSR-containing proteins. The vast majority of these targets are secreted proteins that modulate a variety of extracellular matrix properties that range from modulating cell signaling to tissue flexibility.
Our mouse Pofut2 and B3glct knockout and conditional knockout studies identify a key role for the disaccharide during gastrulation (1) and axis elongation (2) as well as in development of the eye, brain, palate, heart, and musculoskeletal system (unpublished). In humans, loss-of-function mutations in B3GLCT cause in Peters Plus Syndrome (PPS), a congenital disorder characterized by abnormalities in the eye, face, long bones, and digits. Children affected by PPS, often also have developmental delay, cleft palate, and abnormalities in the heart and urogenital system. Our current studies focus on identifying target proteins responsible for the birth defects in B3glct knockout mice, and determining whether loss of the disaccharide affects the folding and trafficking of the target protein. In addition, we want to determine how loss of the sugars affects the function of target proteins and influences tissue interactions and properties of the extracellular matrix.
In isolation, the birth defects that we observe in the mouse B3glct mutants are some of the most common birth defects in humans. This observation suggests that defects in glycosylation of POFUT2 targets or mutations in the target proteins themselves could be cause of the congenital abnormalities in humans. Our mouse studies will provide a foundation for future studies that will evaluate whether the severity and frequency of mouse B3glct mutant abnormalities is influenced by maternal health and nutrition and/or genetic factors. Combined, the outcome of these studies has the potential to make an impact on reducing common birth defects such as hydrocephalus!
1) Du, J., Takeuchi, H., Leonhard-Melief, C., Shroyer, K.R., Dlugosz, M., Haltiwanger, R.S. and Holdener, B.C. (2010) O-Fucosylation of thrombospondin type 1 repeats restricts epithelial to mesenchymal transition (EMT) and maintains epiblast pluripotency during mouse gastrulation. Dev. Biol. 346, 25-38. [PMC2937101]
2) Benz, B., Nandadasa, S., Takeuchi, M., Grady, R.C., Takeuchi, H., LoPilato, R.K., Kakuda, S., Somerville, R.P.T., Apte, S.S., Haltiwanger, R.S., and Holdener, B.C. (2016) Genetic and biochemical evidence that gastrulation defects in Pofut2 mutants result from defects in ADAMTS9 secretion. Dev. Biol. 416, 111-122 . PMCID: PMC5572823.
Siller SS, Sharma H, Li S, Yang J, Zhang Y, Holtzman MJ, Winuthayanon W, Colognato H, Holdener BC, Li FQ, Takemaru KI. (2017) Conditional knockout mice for the distal appendage protein CEP164 reveal its essential roles in airway multiciliated cell differentiation. PLoS Genet. 2017 Dec 15;13(12):e1007128. doi: 10.1371/journal.pgen.1007128. eCollection 2017 Dec. PMID: 29244804 Free PMC Article
Benz BA, Nandadasa S, Takeuchi M, Grady RC, Takeuchi H, LoPilato RK, Kakuda S, Somerville RPT, Apte SS, Haltiwanger RS, and Holdener BC. (2016) Genetic and biochemical evidence that gastrulation defects in Pofut2 mutants result from defects in ADAMTS9 secretion. Dev Biol. doi:10.1016/j.ydbio.2016.05.038
Taibi AV, Lighthouse JK, Grady RC, Shroyer KR, Holdener BC. (2013) Development of a conditional Mesd (mesoderm development) allele for functional analysis of the low-density lipoprotein receptor-related family in defined tissues. PloS one. 2013; 8(10):e75782. PMCID: PMC3790828
Koehler, C, Lighthouse, J.K., Werther, T., Andersen, O.M., Diehl, A., Schnieder, D. Du, J., C Holdener, B.C., Oschkinat, H. (2011) The structure of MESD 45-184 brings light into the mechanism of LDLR family folding. Cell Structure. 9: 337-348. PMID:21397185
Lighthouse, J.K., Zhang, L., Hsieh, J-C., Rosenquist, T., and Holdener, B.C. (2011) MESD is Essential for Apical Localization of Megalin/LRP2 in the Visceral Endoderm. Developmental Dynamics. 240: 577-88. PMID: 21337463
Du, J., Takeuchi, H., Leonhard-Melief, C., Shroyer, K.R., Dlugosz, M., Haltiwanger, R.S., and Holdener, B.C. (2010) O-Fucosylation of Thrombospondin Type 1 Repeats Restricts Epithelial to Mesenchymal Transition (EMT) and Maintains Epiblast Pluripotency During Mouse Gastrulation. Developmental Biology. 346:25-38. PMID: 20637190
J-C. Hsieh, J-C., Lee, L., Zhang, L., Wefer, S., Brown, K., DeRossi, C., Wines, M.E., Rosenquist, T., and Holdener, B.C. (2003) Mesd encodes an LRP5/6 chaperone essential for specification of mouse embryonic polarity. Cell. 112: 355-367. PMID: 12581525
Laiosa, M.D., Lai, Z.W., Thurmond, T.S., Fiore, N.C., DeRossi, C., Holdener, B.C., Gasiewicz, T.A., Silverstone, A.E. (2002) 2,3,7,8-tetrachlorodibenzo-p-dioxin causes alterations in lymphocyte development and thymic atrophy in hemopoietic chimeras generated from mice deficient in ARNT2. Toxicol. Sci. 69:117-124. PMID:12215665
Wines, M.E., Lee, L., Katari, M.S., Zhang, L., DeRossi, C., Shi, Y., Perkins, S., Michael Feldman, M., McCombie, W.R., and Holdener, B.C. (2001) Identification of mesoderm development (mesd) candidate genes by comparative mapping and genome sequence analysis. Genomics. 72: 88-98. PMID:10995574
Michaud, J.L., DeRossi, C., May, N.R., Holdener, B.C., and Fan, C-M. (2000) ARNT2 acts as the dimerization partner of SIM1 for the development of the hypothalamus. Mechanisms of Development 90: 253-261. PMID:10640708
Wines, M., Shi, Y. Lindor, M., and Holdener, B.C. (2000) Physical localization of the mesoderm development (mesd) functional region in mouse. Genomics. 68: 322-329. PMID:9722945
Grimes, J.A., Nielsen, S.J., Battaglioli, E., Miska, E.A., Speh, J.C., Berry, D.L., Atouf, F., Holdener, B.C., Mandel, G., and Tony Kouzarides (2000) The Co-repressor mSin3A is a functional component of the RESTCoREST repressor complex. J. Biol. Chem. 275: 9461-9467. PMID:10734093
Holdener, B.C., Faust, C.J, Rosenthal, N., and Magnuson, T. msd is required for mesoderm induction in mice. (1994) Development. 120: 1335-1346. PMID 8026341