Abnormal FGFR 3 expression in cartilage of thanatophoric dysplasia fetuses
Abnormal FGFR 3 expression in cartilage of thanatophoric dysplasia fetusesAnne-Lise Delezoide1, Catherine Lasselin-Benoist1, Laurence Legeai-Mallet1, Peggy Brice1, Valérie Senée1, Avner Yayon2, Arnold Munnich1, Michel Vekemans1 and Jacky Bonaventure1,*
1Unité de Recherches sur les Handicaps Génétiques de l'Enfant, INSERM U 393, Institut Necker and Assistance publique, Hôpitaux de Paris, 149 rue de Sèvres, 75743 Paris Cedex 15, France and 2Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, 76100 Israel
Received May 30, 1997;Revised and Accepted July 25, 1997
Thanatophoric dysplasia (TD), the commonest lethal skeletal dysplasia in humans, is accounted for by recurrent mutations in the fibroblast growth factor receptor 3 gene (FGFR 3), causing its constitutive activation in vitro. Taking advantage of medical abortion of 18 TD fetuses, cartilage sections were studied for FGFR 3 gene expression by in situ hybridization and immunohistochemistry. Specific antibodies revealed high amounts of FGFR 3 in cartilage of TD fetuses with no increased level of the corresponding mRNA. The specific signal was mainly detected in the nucleus of proliferative and hypertrophic chondrocytes. Based on this observation and the abnormal expression of collagen type X in hypertrophic TD chondrocytes, we suggest that constitutive activation of the receptor through formation of a stable dimer increases its stability and promotes its translocation into the nucleus, where it might interfere with terminal chondrocyte differentiation.
Recurrent mutations of the fibroblast growth factor receptor 3 gene (FGFR 3) have been shown to account for achondroplasia (1 ,2 ), hypochondroplasia (3 ), two clinical forms of thanatophoric dysplasia (TD I and TD II; 4 ,5 ) and several craniosynostosis syndromes (6 ,7 ), suggesting that this gene plays a major role in endochondral and membranous ossification. Subsequently, transfection experiments provided convincing evidence of constitutive activation of the receptor in a ligand-independent manner in chondrodysplasias (8 -10 ). Hitherto, however, the cellular consequences of abnormal gene expression in the growth plate of chondrodysplasia patients have remained poorly understood.
Taking advantage of a series of 18 affected fetuses, we have investigated the pattern of FGFR 3 gene expression in cartilage of TD I and age-matched control fetuses by immunohistochemical and in situ hybridization techniques. Here we report high amounts of FGFR 3 protein in hypertrophic chondrocytes of TD I fetuses, irrespective of the position of FGFR 3 mutations, with no alteration in the amount of FGFR 3 mRNA.
In order to investigate the differential expression of FGFR 3 isoforms (IIIb and IIIc) during development, human probes specific for alternatively spliced exons 8 (IIIb) and 9 (IIIc) were used for in situ hydridization on normal human embryos. At the end of the sixth week of gestation FGFR 3 IIIc transcripts were first detected in the chondrifying mesenchyme (anlage) of the developing limbs, while FGFR 1 transcripts were mostly found in the condensed perichondral mesenchyme (Fig. 1 ). In contrast, no FGFR 3 labeling was observed in the precartilagenous sclerotomal mesenchyme at the early stages of embryogenesis (32-35 days; Fig. 2 ). Both FGFR 3 isoforms were strongly expressed in brain and spinal cord but the type IIIc-specific probe gave a stronger staining and was the only detectable isoform in the mesonephros.
Serial sections revealed a severe disorganization of the cartilage growth plate with a marked reduction of the hypertrophic zone in TD specimens. Since collagen type X expression is a marker of terminal differentiation in normal hypertrophic chondrocytes, we used a COL10A1 probe for studying chondrocyte differentiation in TD specimens. Distribution of COL10A1 transcripts was uneven, as some of the hypertrophic cells displayed no specific signal. Moreover, the proportion of collagen type X-expressing cells was markedly reduced as compared with normal growth plates (Fig. 4 ). In addition, COL10A1 was also expressed in the fibrous band specifically observed in TD patients and disrupting the growth plate. These results were regarded as evidence of markedly disturbed chondrocyte differentiation in TD.
Figure 4. Expression of COL10A1 in the growth plate of control and TD cartilage (bright field and dark field photographs). Hematoxylin-eosin staining of the growth plate of a 24-week-old control fetus (a) and a 27-week-old (number 7, Table 1) TD fetus (d) illustrating disorganization of the growth plate in TD. b, bone; h, hypertrophic chondrocytes; p, proliferative chondrocytes; r, resting chondrocytes. Bright field (b and e) and dark field (c and f) hybridization of serial sections of the same control (b and c) and TD fetus cartilage (e and f) with an antisense riboprobe for COL10A1. Note the low proportion of hypertrophic cells expressing collagen type X in the TD sample. Bars: (a), (b), (d) and (e) 50 [mu]m; (c) and (f) 200 [mu]m.
Staining of serial cartilage sections with an anti-FGFR 3 antibody revealed a stronger signal in TD fetuses, as compared with age-matched controls, both in the hypertrophic and the proliferative zones of the growth plate (Fig. 5 ). Similarly, staining of the perichondrium and resting chondrocytes was more intense and homogeneous in TD fetuses than in age-matched controls. A large amount of immunoreactive material was observed both in the nucleus and cytoplasm of hypertrophic TD chondrocytes, irrespective of the position of FGFR 3 mutations and regardless of the technical procedure for cartilage sectioning (Fig. 5 ). Subsequent in situ hybridization using a FGFR 3 IIIc probe failed to detect significant differences between TD specimens and controls (Fig. 3 h and j), suggesting that the FGFR 3 mutations did not alter the amount of specific mRNA but rather modified turnover of the protein.
Figure 5. Detection of the FGFR 3 protein by immunohistochemical staining of demineralized and non-demineralized tibial cartilage from control and TD fetuses. (a-c) expression of the receptor in the proliferative and hypertrophic chondrocytes of the non-demineralized cartilage growth plate; (a) 24-week-old control fetus; (b and c) TD fetuses 11 and 8 (Table 1). (d and e) FGFR 3 expression in resting chondrocytes and perichondral cells of a 24-week-old control (d) and age-matched TD fetus (number 3, Table 1) demineralized cartilage (e). (f-h) FGFR 3 expression in the proliferative and hypertrophic chondrocytes of the growth plate in demineralized control cartilage (24-week-old fetus) (f) and in the demineralized cartilage of two TD fetuses (numbers 16 and 3, Table 1) (g and h). Note the nuclear and perinuclear staining of hypertrophic TD cells. pe, perichondrium; r, resting chondrocytes; p, proliferative chondrocytes; h, hypertrophic chondrocytes; cj, chondro-osseous junction; vc, vascular canal. Bars (a)-(h) 50 [mu]m.
In the developing mouse FGFR 3 gene expression is first detected in the cartilage rudiments at days 12.5-14.5 p.c. and then restricted to the resting zone during endochondral ossification at day 16 p.c. (11 ). At embryonic day 20 and in the newborn animal the specific transcripts are mainly expressed in the proliferative chondrocytes of the vertebrae (12 ,13 ). An alternative splicing of exons encoding the second half of the third immunoglobulin-like loop was shown to give rise to two isoforms, IIIb and IIIc, in both mouse and human (14 -17 ). Hitherto, however, little was known regarding the pattern of FGFR 3 gene expression during human embryonic development.
Here we report on absent FGFR 3 gene expression in primordial human sclerotomes and its early expression in human brain, spinal cord (5th week) and chondrification centers of developing limbs (6th-7th week of gestation). The present data on FGFR 3 gene expression in the human central nervous system are consistent with the pattern of Fgfr expression in mouse embryos (11 ,18 ,19 ). However, the absence of FGFR 3 expression in prevertebral sclerotomes is at variance with results of animal studies (13 ,20 ). Similarly, in contrast to mouse embryos and newborn mice, the level of gene expression in human ossifying long bones was higher in hypertrophic and proliferative chondrocytes than in the resting zone of the cartilage growth plate, albeit no FGFR 3 expression was observed in terminally differentiating chondrocytes of the chondro-osseous junction. Hence, FGFR 3 expression in hypertrophic human chondrocytes appears to be down-regulated only when resorption of cartilage occurs, i.e. in fully differentiated chondrocytes undergoing cell death. In keeping with this, loss of FGFR 1 expression was demonstrated to be required for terminal differentiation of myogenic cells in chicken limb (21 ). Discrepancies between human and mouse could possibly be accounted for by a higher level of FGFR 1 expression in the hypertrophic zone of mouse cartilage as compared with human and the reduction in FGFR 3 gene expression in mouse hypertrophic chondrocytes might occur earlier than in human. Whether FGFR 1, FGFs or other factors such as BMPs are involved in negative regulation of FGFR 3 expression during skeletal growth is still unknown.
Most interestingly, analysis of the cartilage growth plate using an anti-FGFR 3 antibody detected an intense staining in hypertrophic and proliferative chondrocytes of TD fetuses relative to age-matched controls (with a nuclear and/or perinuclear localization of the receptor). Although variations in the intensity of FGFR 3 staining were noted among TD fetuses, no significant correlation between the position of the mutations and immunohistochemical findings was found. Furthermore, no increased level of specific FGFR 3 mRNA was observed on cartilage sections. The significance of these observations is unclear, but might be related to ligand-independent constitutive dimerization of the receptor through disulfide bonding (9 ,10 ). Stabilization of the mutant receptor in a dimeric form could facilitate its translocation to the nucleus. In keeping with this, stimulation of NIH 3T3 cells by FGF 1 resulted in translocation of the FGFR 1 receptor to the nucleus (22 ) and incubating mouse fibroblasts with FGF 2 resulted in binding of the activated receptor to the nuclear matrix (23 ).
In normal cartilage terminal differentiation of hypertrophic chondrocytes is associated with collagen type X synthesis and programmed cell death. Our observation that only a fraction of hypertrophic chondrocytes expressed collagen type X in TD fetuses suggests that constitutive activation of the receptor interferes with terminal differentiation. This hypothesis is supported by the previous demonstration that application of FGF 2 to rabbit chondrocytes prevented terminal differentiation (24 ). Since achondroplasia and TD mutations consistently activate FGFR 3 by mimicking the presence of ligand, it is tempting to speculate that in TD patients chondrocytes undergo premature apoptosis prior to the hypertrophic stage, leading to reduced skeletal growth. The observation that targeted disruption of Bcl-2 (an anti-apoptotic factor that controls programmed cell death) led to accelerated maturation of chondrocytes with shortening of long bones (25 ) gives additional support to this model and suggests that FGFR 3 mutations alter chondrocyte differentiation rather than proliferation.
.FGFR 3 mutations in thanatophoric dysplasia (TD) fetuses and technical procedures used on cartilage samples
Fetus no.
Gestational age (weeks)
FGFR 3 mutation
In situ hybridization
Immunohistochemistry
demineralized
non demineralized
1
17
Y373C
-
+
-
2
26
J807G
-
+
-
3
27
R248C
-
+
-
4
23
S249C
-
+
-
5
21
J807C
-
+
-
6
19
Y373C
+
-
+
7
27
R248C
+
+
+
8
26
R248C
+
+
+
9
19
R248C
+
+
+
10
24
S249C
+
+
+
11
16
J807R
-
-
+
12
24
Y373C
-
+
-
13
27
n.a.
-
+
-
14
21
n.a.
-
+
-
15
23
n.a.
-
+
-
16
24
Y373C
-
+
-
17
25
R248C
-
+
-
18
21
?
-
+
-
Control fetuses (7) were matched for gestational age in the range 13-35 weeks. No FGFR 3 mutation was found in one TD fetus (18) and no DNAs samples were available (n.a.) for fetuses 13-15.
In situ hybridization using sense and antisense FGFR 3 IIIc and COL10A1 riboprobes were performed in five TD fetuses (6-10).
For immunohistochemical staining, cartilage samples were demineralized or non-demineralized prior to fixation.
Tibial and/or femoral cartilage fragments were obtained from 18 medically aborted TD fetuses following the informed consent of the parents. In all cases pregnancies were legally terminated after ultrasonographic and X-ray detection of severe dwarfism. Histological studies of cartilage sections and molecular detection of FGFR 3 mutations subsequently confirmed the diagnosis of TD I. The control group included spontaneously aborted fetuses showing no evidence of skeletal abnormalities. Embryos were obtained from legally terminated pregnancies according to the French ethical committee recommendations.
Screening of FGFR 3 mutations on either white blood cell or cultured skin fibroblast DNA was performed by SSCP or restriction analyses of amplification products (26 ,27 ). Mutant genotypes included the R248C (5/18), S249C (2/18), Y373C (4/18) and stop codon mutations (3/18) (Table 1 ). DNA from 3/18 cases was not available and we failed to detect FGFR 3 mutations in 1/18 fetuses.
Bone fragments were demineralized by moderate nitric acid treatment for 48 h, then fixed and embedded in paraffin blocks. Other samples were directly fixed with 4% paraformaldehyde then embedded in paraffin. A polyclonal antibody raised against the C-terminal end of human FGFR 3 was purchased from Santa Cruz Biotechnology (Santa Cruz, CA). Its specificity for FGFR 3 has been previously documented (28 ). After a 1 h incubation of the serial sections with the specific antibody at room temperature (dilution 1:20) a streptavidin-biotin complex was added for signal amplification and specific detection was achieved by adding the chromogenic substrate diaminobenzidine. Serial sections were counterstained with methyl green and negative controls were obtained by omitting the specific antibody. A second anti-FGFR 3 antibody kindly provided by A.Yayon gave similar results. Higher antibody dilutions (1/50, 1/100 and 1/200) were tested on both control and TD cartilage sections. No signal was detected in control samples when dilution exceeded 1/50, while TD cells stained positively even at a 1/200 dilution.
Total RNA from cultured human fetal chondrocytes was reverse transcribed using primers specific for the human FGFR 1, FGFR 3 and COL10A1 transcripts and the respective cDNAs were cloned into a pCR3 vector (InVitrogen). The FGFR 3 probe (438 bp) encompassed the extracellular (Ig III loop) and transmembrane domains of the cDNA (nt 860-1298) (29 ). Two additional probes specific for the FGFR 3 IIIb (151 bp) and IIIc alternative transcripts (132 bp) were obtained by PCR amplification of human genomic DNA using exonic primers (16 ). Forward primers: 5'-GATCAGTGAGAGTGTGGAGC-3' (IIIb); 5'-CGCTAACACCACCGACAAGG-3' (IIIc). Reverse primers: 5'-GAACGCTCAGCCAAAAGG-3' (IIIb); 5'-AGCACCACCAGCCACGCA-3' (IIIc). The FGFR 1 probe (363 bp) encompassed part of the extracellular and transmembrane domains (nt 957-1320) (30 ). Finally, primers located in exon 3 of the COL10A1 gene (nt 277-633) (31 ) were used to amplify a 386 bp fragment encompassing part of the triple helical domain. Sequencing of cloned PCR products with the dye terminator sequencing kit (Perkin Elmer) confirmed the originally reported human sequences (29 -31 ).
Sense and antisense riboprobes were generated using either T7 or SP6 RNA polymerases in the presence of [[alpha]-35S]UTP (1200 Ci/mmol; NEN). Labeled probes were purified on Sephadex G50. Hybridization and post-hybridization washes were carried out according to standard protocols. Slides were dehydrated, dipped in Kodak NTB 2 emulsion, exposed for 10-20 days, then developed and counterstained with methyl green. The results were analyzed by dark and bright field microscopy.
We wish to thank A.Beauvais and C.Esculpavit for technical assistance. Embryos and fetuses were kindly provided by E.Aubeni, C.Fallet-Bianco, F.Menez, F.Narcy and R.Taurelle. This work was supported by the Association Française contre les Myopathies (AFM) and an APHP-DRC contract (CRC 96146).
1 Rousseau,F., Bonaventure,J., Legeai-Mallet,L., Pelet,A., Rozet,J.M., Maroteaux,P., Le Merrer,M. and Munnich,A. (1994) Mutations in the gene encoding fibroblast growth factor receptor 3 in achondroplasia. Nature, 371, 252-254.MEDLINE Abstract
2 Shiang,R., Thompson,L.M., Zhu,Y.Z., Church,D.M., Fielder,T.J., Bocian,M., Winokur,S.T. and Wasmuth,J.J. (1994) Mutations in the transmembrane domain of FGFR 3 cause the most common genetic form of dwarfism achondroplasia. Cell, 78, 336-342.
3 Bellus,G.A., McIntosh,I., Smith,A.E., Aylsworth,A.S., Kaitila,I., Horton,W., Greenhaw,G.A., Hecht,J.T. and Francomano,C. (1995) A recurrent mutation in the tyrosine kinase domain of fibroblast growth factor receptor 3 causes hypochondroplasia. Nature Genet., 10, 357-359.MEDLINE Abstract
4 Rousseau,F., Saugier,P., Le Merrer,M., Munnich,A., Delezoide,A.L., Maroteaux,P. and Bonaventure,J. (1995) Stop codon FGFR 3 mutations in thanatophoric dwarfism type I. Nature Genet., 10, 11-12.MEDLINE Abstract
5 Tavormina,P.L., Shiang,R., Thompson,L., Zhu,Y.Z., Wilkin,D.J., Lachman,R., Wilcox,W.R., Rimoin,D., Cohn,D. and Wasmuth,J.J. (1995) Thanatophoric dysplasia (types I and II) caused by distinct mutations in fibroblast growth factor receptor 3. Nature Genet., 9, 321-328.MEDLINE Abstract
6 Meyers,G.A., Orlow,S.J., Munro,I.R., Przylepa,K.A. and Jabs,E.W. (1995) Fibroblast growth factor receptor 3 (FGFR 3) transmembrane mutation in Crouzon syndrome with acanthosis nigricans. Nature Genet., 11, 462-464.MEDLINE Abstract
7 Bellus,G.A. Gaudenz,K., Zackai,E.H., Clarke,L.A., Szabo,J., Francomano,C. and Muenke,M. (1996) Identical mutations in three fibroblast growth factor receptor genes in autosomal dominant craniosynostosis syndromes. Nature Genet., 14, 174-176.
8 Webster,M. and Donoghue,D.J. (1996) Constitutive activation of fibroblast growth factor receptor 3 by the transmembrane domain point mutation found in achondroplasia. EMBO J., 15, 520-527.MEDLINE Abstract
9 Naski,M.C., Wang,Q., Xu,J. and Ornitz,D. (1996) Graded activation of fibroblast growth factor receptor 3 by mutations causing achondroplasia and thanatophoric dysplasia. Nature Genet., 13, 233-237.MEDLINE Abstract
10 Webster,M.K., d'Avis,P.Y., Robertson,S.C. and Donoghue,D.J. (1996) Profound ligand-independent kinase activation of fibroblast growth factor receptor 3 by the activation loop mutation responsible for a lethal skeletal dysplasia, thanatophoric dysplasia type II. Mol. Cell. Biol., 16, 4081-4087.MEDLINE Abstract
11 Peters,K., Ornitz,D., Werner,S. and Williams,L. (1993) Unique expression of the FGF receptor 3 gene during mouse organogenesis. Dev. Biol., 155, 423-430.MEDLINE Abstract
12 Deng,C., Wynshaw-Boris,A., Zhou,F., Kuo,A. and Leder,P. (1996) Fibroblast growth factor receptor 3 is a negative regulator of bone growth. Cell, 84, 911-921.MEDLINE Abstract
13 Wuechner,C., Sandberg Nordqvist,A.-C., Winterpacht,A., Zabel,B. and Schalling,M. (1996) Developmental expression of splicing variants of fibroblast growth factor receptor 3 (FGFR 3) in mouse. Int. J. Dev. Biol., 40, 1185-1188.MEDLINE Abstract
14 Werner,S., Weinberg,W., Liao,X., Peters,K., Blessing,M., Yuspa,S.H., Weiner,R.L. and Williams,L. (1993) Targeted expression of a dominant-negative FGF receptor mutant in the epidermis of transgenic mice reveals a role of FGF in keratinocyte organization and differentiation. EMBO J., 12, 2635-2643.MEDLINE Abstract
15 Chellaiah,A., Mc Ewen,D.G., Werner,S., Xu,J. and Ornitz,D. (1994) Fibroblast growth factor receptor (FGFR) 3. Alternative splicing in immunoglobulin-like domain III creates a receptor highly specific for acidic FGF/FGF-1. J. Biol. Chem., 269, 11620-11627.MEDLINE Abstract
16 Scotet,E. and Houssaint,E. (1995) The choice between alternative IIIb and IIIc exons of the FGFR-3 gene is not strictly tissue-specific. Biochim. Biophys. Acta, 1264, 238-242.MEDLINE Abstract
17 Avivi,A., Yayon,A. and Givol,D. (1993) A novel form of FGF receptor-3 using an alternative exon in the immunoglobulin domain III. FEBS Lett., 330, 249-252.MEDLINE Abstract
18 Orr-Urtreger,A., Givol,D., Yayon,A., Yarden,Y. and Lonai,P. (1991) Developmental expression of two murine fibroblasts growth factor receptors flg and bek. Development, 113, 1419-1434.MEDLINE Abstract
19 Peters,K.G., Werner,S., Chen,G. and Williams,L.T. (1992) Two FGF receptor genes are differentially expressed in epithelial and mesenchymal tissues during limb formation and organogenesis in the mouse. Development, 114, 233-243.MEDLINE Abstract
20 Patstone,G., Pasquale,E.B. and Maher,P.A. (1993) Differrent members of the fibroblast growth factor receptor family are specific to distinct cell types in the developing chicken embryo. Dev Biol., 155, 107-123.MEDLINE Abstract
21 Itoh,N., Mima,T. and Mikawa,T. (1996) Loss of fibroblast growth factor receptors is necessary for terminal differentiation of embryonic limb muscle. Development, 122, 291-300.MEDLINE Abstract
22 Prudovsky,I., Savion,N., Zhan,X., Friesel,R., Xu,J., Hou,J., McKeehan,W.L. and Maciag,T (1994) Intact and functional fibroblast growth factor (FGF) receptor 1 trafficks near the nucleus in response to FGF-1. J. Biol. Chem., 269, 31720-31724.MEDLINE Abstract
23 Maher,P.A. (1996) Nuclear translocation of fibroblast growth factor (FGF) receptors in response to FGF 2. J. Cell Biol., 134, 529-536.MEDLINE Abstract
24 Kato,Y. and Iwamoto,M. (1990) Fibroblast growth factor is an inhibitor of chondrocyte terminal differentiation. J. Biol. Chem., 265, 5903-5909.MEDLINE Abstract
25 Amling,M., Neff,L., Tanaka,S., Inoue,D., Kuida,K., Weir,E., Philbrick,W.M., Broadus,A.E. and Baron,R. (1997) Bcl 2 lies downstream of parathyroid hormone related peptide in a signaling pathway that regulates chondrocyte maturation during skeletal development. J. Cell Biol., 136, 205-213.MEDLINE Abstract
26 Rousseau,F., El Ghouzzi,V., Delezoide,A.L., Legeai-Mallet,L., Le Merrer,M., Munnich,A. and Bonaventure,J. (1996) Missense FGFR 3 mutations create cysteine residues in thanatophoric dwarfism type 1 (TD 1). Hum. Mol. Genet., 5, 509-512.MEDLINE Abstract
27 Bonaventure,J., Rousseau,F., Legeai-Mallet,L., Le Merrer,M., Munnich,A. and Maroteaux,P. (1996) Common mutations in the fibroblast growth factor receptor 3 (FGFR 3) gene account for achondroplasia, hypochondroplasia and thanatophoric dwarfism. Am. J. Med. Genet., 63, 148-154.MEDLINE Abstract
28 Johnston,C.L., Cox,H.C., Gomm,J. and Coombes,R.C. (1995) Fibroblast growth factor receptors (FGFRs) localize in different cell compartment. A splice variant of FGFR 3 localizes to the nucleus. J. Biol. Chem., 276, 30643-30650.
29 Keegan,K., Johnson,D., Williams,L. and Hayman,M. (1991) Isolation of an additional member of the fibroblast growth factor receptor family, FGFR 3. Proc. Natl. Acad. Sci. USA, 88, 1095-1099.MEDLINE Abstract
30 Isacchi,A., Bergonzoni,L. and Sarmientos,P. (1990) Complete sequence of a human receptor for acidic and basic fibroblast growth factors. Nucleic Acid Res., 18, 1906.MEDLINE Abstract
31 Thomas,J.T., Cresswell,C.J., Rash,B., Nicolai,H., Jones,T., Salomon,E., Grant,M.E. and Boot-Hanford,R.P. (1991) The human collagen X gene. Complete primary translated sequence and chromosomal localization. Biochem. J., 280, 141-148.
J. Y. Cho, C. Guo, M. Torello, G. P. Lunstrum, T. Iwata, C. Deng, and W. A. Horton Defective lysosomal targeting of activated fibroblast growth factor receptor 3 in achondroplasia
PNAS,
January 13, 2004;
101(2):
609 - 614.
[Abstract][Full Text][PDF]
S. Cormier, A.-L. Delezoide, C. Benoist-Lasselin, L. Legeai-Mallet, J. Bonaventure, and C. Silve Parathyroid Hormone Receptor Type 1/Indian Hedgehog Expression Is Preserved in the Growth Plate of Human Fetuses Affected with Fibroblast Growth Factor Receptor Type 3 Activating Mutations
Am. J. Pathol.,
October 1, 2002;
161(4):
1325 - 1335.
[Abstract][Full Text][PDF]
T. Iwata, C.-L. Li, C.-X. Deng, and C. A. Francomano Highly activated Fgfr3 with the K644M mutation causes prolonged survival in severe dwarf mice
Hum. Mol. Genet.,
June 1, 2001;
10(12):
1255 - 1264.
[Abstract][Full Text][PDF]
J. J. Wysolmerski, S. Cormier, W. M. Philbrick, P. Dann, J.-P. Zhang, J. Roume, A.-L. Delezoide, and C. Silve Absence of Functional Type 1 Parathyroid Hormone (PTH)/PTH-Related Protein Receptors in Humans Is Associated with Abnormal Breast Development and Tooth Impaction
J. Clin. Endocrinol. Metab.,
April 1, 2001;
86(4):
1788 - 1794.
[Abstract][Full Text]
O. Segev, I. Chumakov, Z. Nevo, D. Givol, L. Madar-Shapiro, Y. Sheinin, M. Weinreb, and A. Yayon Restrained chondrocyte proliferation and maturation with abnormal growth plate vascularization and ossification in human FGFR-3G380R transgenic mice
Hum. Mol. Genet.,
January 22, 2000;
9(2):
249 - 258.
[Abstract][Full Text][PDF]
E. Monsonego-Ornan, R. Adar, T. Feferman, O. Segev, and A. Yayon The Transmembrane Mutation G380R in Fibroblast Growth Factor Receptor 3 Uncouples Ligand-Mediated Receptor Activation from Down-Regulation
Mol. Cell. Biol.,
January 15, 2000;
20(2):
516 - 522.
[Abstract][Full Text]
D. Grisaru, E. Lev-Lehman, M. Shapira, E. Chaikin, J. B. Lessing, A. Eldor, F. Eckstein, and H. Soreq Human Osteogenesis Involves Differentiation-Dependent Increases in the Morphogenically Active 3' Alternative Splicing Variant of Acetylcholinesterase
Mol. Cell. Biol.,
January 1, 1999;
19(1):
788 - 795.
[Abstract][Full Text][PDF]