Molecular Pathogenesis of Bernard-Soulier Syndrome

ABSTRACT

Bernard-Soulier syndrome (BSS), a hereditary qualitative platelet disorder, is now proved to be caused by a qualitative or quantitative abnormality of the platelet glycoprotein (GP) Ib/IX/V complex. We investigated the genetic background of two Japanese females with BSS and identified the molecular defects underlying this disease. The first case was a single base pair deletion within seven adenine repeats at position 4464-4470 (EMBL, no. M22403) of the GPIbα gene resulting in a frameshift and a premature stop codon. The second case was a single T→C substitution at nucleotide 1856 (EMBL, no. M80478) of the GPIX gene resulting in Phe⁵⁵ (TTT)→Ser(TCT) substitution. The latter case is of interest in considering the pathogenesis of BSS, because all four GPs consisting of the GPIb/IX/V complex have the same structural unit called leucine-rich repeat (LRR). Because this mutation is located within the LRR of the GPIX polypeptide, Phe⁵⁵→Ser substitution may result in an alteration of the LRR that leads to impaired surface expression of the GPIb/IX/V complex. To clarify the effect of this mutation on surface expression of the GPIb/IX complex, we performed transfection studies with a plasmid having this mutation. Mutant GPIX could not increase surface expression of the GPIb/IX complex, thus demonstrating an important role of the LRR of the GPIX polypeptide during biosynthesis.

KEYWORD

Bernard-Soulier syndrome - platelet glycoprotein - GPIb/IX/V complex - leucine-rich repeat - missense mutation

REFERENCES

• 1 Bernard J, Soulier J P. Sur une nouvelle varitété de dystrophie thrombocytaire hémorragipare cogénitale.  Semin H(tm)pital Paris . 1948;  24 3217-3223
• 2 Coller B S. Hereditary qualitative platelet disorder. In: Beutler E, Lichtman MA, Coller BS, Kipps TJ, eds. Williams Hematology, 5th ed New York: McGraw-Hill, 1995: 1372-1374
• 3 Ruggeri Z M. Glycoprotein Ib and von Willebrand factor in the process of the thrombus formation.  Ann NY Acad Sci . 1994;  714 200-210
• 4 Ikeda Y, Handa M, Kawano K. The role of von Willebrand factor and fibrinogen in platelet aggregation under varying shear stress.  J Clin Invest . 1991;  87 1234-1240
• 5 Harmon J T, Jamieson G A. The glycocalicin portion of platelet glycoprotein Ib expresses both high and moderate affinity receptor sites for thrombin. A soluble radioreceptor assay for the interaction of thrombin with platelets.  J Biol Chem . 1986;  261 13224-13229
• 6 De Marco L, Mazzucato M, Masotti A, Fenton II W J, Ruggeri Z M. Function of glycoprotein Ibα in platelet activation induced by α-thrombin.  J Biol Chem . 1991;  266 23776-23783
• 7 Roth G J. Developing relationship: Arterial platelet adhesion, glycoprotein Ib, and leucine-rich glycoprotein.  Blood . 1991;  77 5-19
• 8 Takahashi N, Takahashi Y, Putnum F W. Periodicity of leucine and tandem repetition of a 24-amino acid segment in the primary structure of leucine-rich alpha 2-glycoprotein of human serum.  Proc Natl Acad Sci USA . 1985;  82 19006-1910
• 9 Nurden A T, Didry D, Rosa J P. Molecular defects of platelets in Bernard-Soulier syndrome.  Blood Cells . 1983;  9 333-358
• 10 Drouin J, McGregor J L, Parmentier S, Izaguirre C A, Clemetson K J. Residual amounts of glycoprotein Ib concomitant with near-absence of glycoprotein IX in platelets of Bernard-Soulier patients.  Blood . 1988;  72 1086-1088
• 11 Stevens M C, Blanchette V S, Freedman M H, Sparling C, Kunicki T J. A variant form of Bernard-Soulier syndrome: Mild haemostatic defect associated with partial platelet GPIb deficiency.  Clin Lab Haematol . 1988;  10 443-451
• 12 Finch C N, Miller J L, Lyle V A, Handin R I. Evidence that an abnormality in the glycoprotein Ib alpha gene is not the cause of abnormal platelet function in a family with classic Bernard-Soulier disease.  Blood . 1990;  75 2357-2362
• 13 Poulsen L O, Taaning E. Variation in surface platelet glycoprotein Ib expression in Bernard-Soulier syndrome.  Haemostasis . 1990;  20 155-161
• 14 Lopez J A, Leung B, Reynolds C C, Li C Q, Fox J E. Efficient plasma membrane expression of a functional platelet glycoprotein Ib-IX complex requires the presence of its three subunits.  J Biol Chem . 1992;  267 12851-12859
• 15 Suzuki K, Hayashi T, Yahagi A. Novel point mutation in the leucine-rich motif of the platelet glycoprotein IX associated with Bernard-Soulier syndrome.  Br J Haematol . 1997;  99 794-800
• 16 Mitsui T, Yokoyama S, Yazaki N. Severe bleeding tendency in a patient with Bernard-Soulier syndrome associated with a homozygous single base pair deletion in the gene coding for the human platelet glycoprotein Ibα.  J Pediatr Hematol Oncol . 1998;  20 246-251
• 17 Blin N, Stafford D W. A general method for isolation of high molecular weight DNA from eukaryocytes.  Nucleic Acids Res . 1976;  3 2303-2308
• 18 Simsek S, Admiraal L G, Modderman P W, van der Schoot E C, von dem Borne A G K E. Identification of a homozygous single base pair deletion in the gene coding for the human platelet glycoprotein Ib alpha causing Bernard-Soulier syndrome.  Thromb Haemost . 1994;  72 444-449
• 19 Li C, Martin S E, Roth G J. The genetic defect in two well-studied cases of Bernard-Soulier syndrome: A point mutation in the fifth leucine-rich repeat of platelet glycoprotein Ib alpha.  Blood . 1995;  86 3805-3814
• 20 Sanger F, Nicklen S, Coulson A R. DNA sequencing with chain-terminating inhibitors.  Proc Natl Acad Sci USA . 1977;  74 5463-5467
• 21 Kunkel T A, Roberts J D, Zakour R A. Rapid and efficient site-specific mutagenesis without phenotypic selection.  Methods Enzymol . 1987;  154 367-383
• 22 Du X, Beutler L, Ruan C, Castaldi P A, Berndt M C. Glycoprotein Ib and glycoprotein IX are fully complexed in the intact platelet membrane.  Blood . 1987;  69 1524-1527
• 23 Suzuki K, Hayashi T, Akiba J, Satoh S, Kato T. Phenotypic consequence of the gene abnormality in the platelet glycoprotein IX gene observed in a patient with Bernard-Soulier syndrome through mammalian cell expression system.  Thromb Res . 1999;  95 295-302
• 24 Kobe B, Deisenhofer J. Crystal structure of porcine ribonuclease inhibitor, a protein with leucine-rich repeats.  Nature . 1993;  366 751-756
• 25 Sae-Tung G, Dong J F, Lopez J A. Biosynthetic defect in platelet glycoprotein IX mutants associated with Bernard-Soulier syndrome.  Blood . 1996;  87 1361-1367
• 26 Gay N J, Packman L C, Weldon M A, Barna J C. A leucine-rich repeat peptide derived from the Drosophila Toll receptor forms extended filaments with a β-sheet structure.  FEBS Lett . 1991;  291 87-91
• 27 Krantz D D, Zidovetzki R, Kagan B L, Zipursky S L. Amphipathic β structure of a leucine-rich repeat peptide.  J Biol Chem . 1991;  266 16801-16807
• 28 Kishimoto T K, Hollander N, Roberts T M, Anderson D C, Springer T A. Heterogeneous mutations in the beta subunit common to the LFA-1, Mac-1, and p150/95 glycoproteins cause leukocyte adhesion deficiency.  Cell . 1987;  50 193-202
• 29 O'Toole T E, Loftus J C, Plow E F. Efficient surface expression of platelet GPIIb-IIIa requires both subunits.  Blood . 1989;  74 14-18.
• 30 Miller J L. Platelet-type von Willebrand disease.  Thromb Haemost . 1996;  75 865-869