F. Bonnet

Amino acid sequence of the Homo sapiens brain 21-23-kDa protein (Neuropolypeptide h3), Comparison with its counterparts from Rattus norvegicus and Bos taurus species, and expression of its mRNA in different tissues

The amino acid sequence of neuropolypeptide h3 from Homo sapiens brain has been determined. It revealed that h3 is the exact counterpart of the 21-kDa protein from Bos taurus brain and the 23-kDa protein from Rattus norvegicus brain: The three proteins belong to the same 21-23-kDa protein family. Multiple tissue Northern blots showed that the mRNA encoding the 21-23-kDa protein is expressed in different amounts according to tissues and species; it is particularly abundant in Rattus norvegicus testis.

An unexpected sequence homology between link proteins of the proteoglycan complex and immunoglobulin-line proteins

The N-terminal sequence (residues 1-101) of trypsin-link protein from cartilage proteoglycan complex is reported: it presents structural homologies with the poly-Ig receptor and immunoglobulin domains.

Complete amino acid sequence of a human platelet proteoglycan

The primary structure of a human platelet proteoglycan (P.PG) core was established by a combination of amino acid sequence analysis and cDNA cloning. The deduced 131 amino acid long protein contains eight Ser‐Gly repeats. The significance of homologies observed between P.PG and promyelocytic leukemia cell line proteoglycans is discussed.

Sequence data concerning the protein core of the cartilage proteoglycan monomers. Characterization of a sequence allowing the synthesis of an oligonucleotide probe.

The present report develops our previous structural data concerning the cyanogen bromide fragments from the bovine nasal cartilage proteoglycan monomers. Among the reported sequences a Met‐Ile‐Trp‐His sequence was characterized, useful for future studies devoted to the molecular cloning of the proteoglycan monomers.

Identification of cyanogen bromide-fragments of the protein core of bovine nasal cartilage proteoglycan monomer

Cyanogen bromide treatment of bovine nasal cartilage proteoglycan monomer gave rise to three major fractions (CN-1 to CN-3), isolated by Sepharose CL-6B chromatography. The uronate-rich fraction in the void volume (CN-1) digested with chondroitinase ABC (C treatment) yielded a fragment (CN-1 C/6B) with a unique N-terminal sequence. The same fraction, when digested sequentially by chondroitinase ABC and trypsin (CT treatment), was resolved into two distinct fractions, CN-1 CT/6B-1 and CN-1 CT/6B-2. CN-1 CT/6B-1 consisted in a keratan sulfate-rich region, representing the N-terminal moiety of the CN-1 fraction; these data suggested, according to the model of the proteoglycan monomer structure described by Heinegard, D. and Axelsson, I. (1977) J. Biol. Chem. 252, 1971-1979, that its C-terminal moiety is localized at the end of the core bearing the chondroitin sulfate chains. CN-1 CT/6B-2 contained two fragments from the chondroitin sulfate-bearing region: one of them has been submitted to Edman degradation. The CN-2 fraction upon chondroitinase and trypsin treatments gave rise to a keratan-bearing region (CN-2 CT/6B-1) and a mannose-rich region (CN-2 CT/6B-2). After reduction and alkylation of CN-2, the N-terminal sequence of the isolated major fragment (CN-2 RA/6B-1) was determined. The CN-3 fraction revealed a pattern upon electrophoresis similar to that of the cyanogen bromide-treated hyaluronic acid-binding region.

Structural relationship between link proteins and proteoglycan monomers

Structural homologies between link proteins and proteoglycan monomers are demonstrated. A possible redundancy in the proteoglycan monomers structure is discussed and the link proteins domains homologous to other proteins are specified.

The action of trypsin on purified link proteins from bovine nasal cartilage proteoglycan complex

1. Introduction Two major proteins, termed link proteins a and b, are present in bovine nasal cartilage complex [I]. A ‘T-G 200-3’ fraction from a chondroitinase-trypsin digest of a proteoglycan complex fraction which was able to bind hyaluronic acid was isolated [2]. It was postulated that this ‘T-G 200-3’ protein might be derived from the smaller link protein a. The present note deals with the action of trypsin on the purified a and b link proteins [3]. 2. Materials and methods 2.1.

Localization of human platelet proteoglycan gene to chromosome 10, band q22.1, by in situ hybridization

SummaryA cDNA probe of 527 base pairs coding for the human platelet proteoglycan (PPG) protein core demonstrated that the PPG gene lies on the long arm of chromosome 10, band q22.1. This result and other available data concerning proteoglycans containing serine-glycine repeats indicate that this gene is involved in the expression of a proteoglycan in various blood cell types.

Proteoglycan complex and proteoglycan subunit polydispersity. Study by isopycnic centrifugation in cesium sulfate density gradients

A true isopycnic centrifugation method for the study of the bovine nasal cartilage proteoglycan polydispersity is presented. The use of cesium sulfate as gradient forming salt instead of cesium chloride allowed proteoglycan banding without any sedimentation at the bottom of the centrifuge tube. Apparent buoyant densities of proteoglycan monomer and proteoglycan aggregate were different. The present method provides a useful tool for the study of proteoglycan polydispersity and also allows us to follow the distribution of the link proteins in different proteoglycan extracts.

Comparative studies on human and bovine nasal cartilage proteoglycan complex components.

SummaryHuman and bovine nasal proteoglycan complex components were prepared in parallel. Some molecular properties of human and bovine proteoglycan subunits (PGS) were compared. Two major human “link-like proteins” have been characterized and purified; their compositions and molecular weights were very similar to those observed for the previously described bovine “link proteins”.