Normal skeletal development of mice lacking matrilin 1: Redundant function of matrilins in cartilage?

Abstract

Matrilin 1, or cartilage matrix protein, is a member of a novel family of extracellular matrix proteins. To date, four members of the family have been identified, but their biological role is unknown. Matrilin 1 and matrilin 3 are expressed in cartilage, while matrilin 2 and matrilin 4 are present in many tissues. Here we describe the generation and analysis of mice carrying a null mutation in the Crtm gene encoding matrilin 1. Anatomical and histological studies demonstrated normal development of homozygous mutant mice. Northern blot and biochemical analyses show no compensatory up- regulation of matrilin 2 or 3 in the cartilage of knockout mice. Although matrilin 1 interacts with the colla..