Mice lacking the extracellular matrix adaptor protein matrilin-2 develop without obvious abnormalities.
Matrilins are putative adaptor proteins of the extracellular matrix (ECM) which can form both collagen-dependent and collagen-independent filamentous networks. While all known matrilins (matrilin-1, -2, -3, and -4) are expressed in cartilage, only matrilin-2 and matrilin-4 are abundant in non-skeletal tissues. To clarify the biological role of matrilin-2, we have developed a matrilin-2-deficient mouse strain. Matrilin-2 null mice show no gross abnormalities during embryonic or adult development, are fertile, and have a normal lifespan. Histological and ultrastructural analyses indicate apparently normal structure of all organs and tissues where matrilin-2 is expressed. Although matrilin-2 co-localizes with matrilin-4 in many tissues, Northern hybridization, semiquantitative RT-PCR, immunohistochemistry and biochemical analysis reveal no significant alteration in the steady-state level of matrilin-4 expression in homozygous mutant mice. Immunostaining of wild-type and mutant skin samples indicate no detectable differences in the expression and deposition of matrilin-2 binding partners including collagen I, laminin-nidogen complexes, fibrillin-2 and fibronectin. In addition, electron microscopy reveals an intact basement membrane at the epidermal-dermal junction and normal organization of the dermal collagen fibrils in mutant skin. These data suggest that either matrilin-2 and matrilin-2-mediated matrix-matrix interactions are dispensable for proper ECM assembly and function, or that they are efficiently compensated by other matrix components including wild-type levels of matrilin-4.
Institute of Biochemistry, Biological Research Center of the Hungarian Academy of Sciences, H-6701 Szeged, Hungary.
Lajos
L
Mátés
Claudia
C
Nicolae
Matthias
M
Mörgelin
Ferenc
F
Deák
Ibolya
I
Kiss
Attila
A
Aszódi
D000818:Animals; D001846:Bone Development; D024042:Collagen Type I / Q000378:metabolism; D024141:Collagen Type IV / Q000378:metabolism; D004622:Embryo, Mammalian / Q000196:embryology / Q000378:metabolism*; D016326:Extracellular Matrix Proteins / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D000071840:Fibrillin-2; D000071837:Fibrillins; D005353:Fibronectins / Q000378:metabolism; D006023:Glycoproteins / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D007403:Intervertebral Disc / Q000196:embryology / Q000254:growth & development; D007797:Laminin / Q000378:metabolism; D008024:Ligands; D064235:Matrilin Proteins; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout; D008840:Microfilament Proteins / Q000378:metabolism; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D012867:Skin / Q000378:metabolism
D024042:Collagen Type I; D024141:Collagen Type IV; D016326:Extracellular Matrix Proteins; C000605728:Fbn2 protein, mouse; D000071840:Fibrillin-2; D000071837:Fibrillins; D005353:Fibronectins; D006023:Glycoproteins; D007797:Laminin; D008024:Ligands; C577542:Matn2 protein, mouse; D064235:Matrilin Proteins; D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; C029967:nidogen