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R Deutzmann

Publications and source records attributed to R Deutzmann.

At least 55 records · Page 3Linked to original sources
PubMed1990

Identification of the Arg-Gly-Asp sequence in laminin A chain as a latent cell-binding site being exposed in fragment P1.

A single RGD-containing sequence present within an epidermal growth factor-like repeat of the short arms of laminin is shown by peptide inhibition to block integrin receptors recognizing a latent cell-binding site of laminin. Based on proteolysis data it is proposed that masking occurs by folding of the globular domain IVa over the cell-binding site in the adjacent rod-like structures of laminin A chain.

Binding Sites↗
PubMed1990

Transient and locally restricted expression of laminin A chain mRNA by developing epithelial cells during kidney organogenesis.

Three polypeptide chains, A, B1, and B2, have been described for mouse laminin, a basement membrane protein. We studied expression of laminin A, B1, and B2 mRNA in the developing mouse kidney. Induction of kidney mesenchyme differentiation in vitro led to an increased expression of B1 and B2 chain mRNA on day 1 of development. In contrast, expression of A chain mRNA increased on day 2, when epithelial cell polarization begins. Laminin A mRNA and polypeptide were expressed only by epithelia during in vivo development as well. Some polarized cell types producing basement membrane (endothelium, some adult epithelia) lacked the A chain mRNA and polypeptide, although they did express B chains. Laminin with the 400 kd A chain is therefore a transient form appearing at specific sites of kidney morphogenesis, whereas isoforms with a different A chain or without it have a more widespread distribution.

Animals↗
PubMed1990

Mosaic structure of globular domains in the human type VI collagen alpha 3 chain: similarity to von Willebrand factor, fibronectin, actin, salivary proteins and aprotinin type protease inhibitors.

Human collagen alpha 3(VI) chain mRNA (approximately 10 kb) was cloned and shown by sequence analysis to encode a 25 residue signal peptide, a large N-terminal globule (1804 residues), a central triple helical segment (336 residues) and a C-terminal globule (803 residues). Some of the sequence was confirmed by Edman degradation of peptides. The N-terminal globular segment consists of nine consecutive 200 residue repeats (N1 to N9) showing internal homology and also significant identity (17-25%) to the A domains of von Willebrand Factor and similar domains present in some other proteins. Deletions were found in the N3 and N9 domains of several cDNA clones suggesting variation of these structures by alternative splicing. The C-terminal globule starts immediately after the triple helical segment with two domains C1 (184 residues) and C2 (248 residues) being similar to the N domains. They are followed by a proline rich, repetitive segment C3 of 122 residues, with similarity to some salivary proteins, and domain C4 (89 residues), which is similar to the type III repeats present in fibronectin and tenascin. The most C-terminal domain C5 (70 residues) shows 40-50% identity to a variety of serine protease inhibitors of the Kunitz type. The whole sequence contains 29 cysteines which are mainly clustered in short segments connecting domains N1, C1, C2 and the triple helix, and in the inhibitor domain. Five putative Arg-Gly-Asp cell-binding sequences are exclusively localized in the triple helical segment.(ABSTRACT TRUNCATED AT 250 WORDS)

Actins↗
PubMed1990

Anchorin CII, a collagen-binding chondrocyte surface protein of the calpactin family.

In an attempt to identify collagen-binding proteins on the chondrocyte surface, a protein of Mr 34KD, called Anchorin CII was isolated from chondrocyte membranes by affinity chromatography on type II collagen sepharose (Mollenhauer & von der Mark, 1983). The protein was localized on the chondrocyte surface by immunofluorescence labeling using a specific rabbit antibody (Mollenhauer et al., 1984), by immunogold labeling and by cell surface iodination (Pfäffle et al., 1988). Fab'fragments of anti anchorin CII reduced the binding of chondrocytes to type II collagen substrates (Mollenhauer et al., 1984). Analysis of the complete primary structure of anchorin CII revealed 4 repetitive domains of each 70-80 amino acid residues, and the absence of hydrophobic transmembrane sequences or signal peptides (Fernández et al., 1988). Thus, anchorin CII is another member of the calpactin/lipocortin/annexin family, although most other members of this family are located strictly intracellularly. Similar to lipocortin I, however, anchorin CII can be identified extracellularly, e.g. in the culture medium of chondrocytes and fibroblasts (Pfäffle et al., 1988). Here we report on further studies on sequence homologies to other annexins, and on the Ca(++)- and phospholipide binding of this protein.

Amino Acid Sequence↗
PubMed1989

N-terminal amino acid sequence of the Borrelia burgdorferi flagellin.

The 41 kDa flagellar protein of Borrelia burgdorferi appears to be an immunodominant antigen producing an early and strong response in most, if not all, individuals during infection in humans. It would represent a very good antigen for serodiagnosis of Lyme disease, if its crossreactivity with flagella of other bacteria was low. To gain information on this point we isolated the B. burgdorferi flagellin by preparative two-dimensional electrophoresis for N-terminal amino acid analysis. By comparing the N-terminal amino acid sequences of flagellar proteins from other eubacteria we found that the first six out of twenty nine amino acids were identical to the Treponema pallidum and Treponema phagedenis 'class B' flagellins. All 29 N-terminal residues exhibited a moderate inter-genus homology (44-55%), in contrast to the high degree (67-95%) of inter-species conservation of the treponemal 'class B' flagellar N-terminal sequences. There was little similarity to other flagellins except the B. subtilis flagellar protein.

Amino Acid Sequence↗
PubMed1989

Amino acid sequence of mouse nidogen, a multidomain basement membrane protein with binding activity for laminin, collagen IV and cells.

The whole amino acid sequence of nidogen was deduced from cDNA clones isolated from expression libraries and confirmed to approximately 50% by Edman degradation of peptides. The protein consists of some 1217 amino acid residues and a 28-residue signal peptide. The data support a previously proposed dumb-bell model of nidogen by demonstrating a large N-terminal globular domain (641 residues), five EGF-like repeats constituting the rod-like domain (248 residues) and a smaller C-terminal globule (328 residues). Two more EGF-like repeats interrupt the N-terminal and terminate the C-terminal sequences. Weak sequence homologies (25%) were detected between some regions of nidogen, the LDL receptor, thyroglobulin and the EGF precursor. Nidogen contains two consensus sequences for tyrosine sulfation and for asparagine beta-hydroxylation, two N-linked carbohydrate acceptor sites and, within one of the EGF-like repeats an Arg-Gly-Asp sequence. The latter was shown to be functional in cell attachment to nidogen. Binding sites for laminin and collagen IV are present on the C-terminal globule but not yet precisely localized.

Amino Acid Sequence↗
PubMed1989

Sequence analysis of alpha 1(VI) and alpha 2(VI) chains of human type VI collagen reveals internal triplication of globular domains similar to the A domains of von Willebrand factor and two alpha 2(VI) chain variants that differ in the carboxy terminus.

Amino acid sequences of human collagen alpha 1(VI) and alpha 2(VI) chains were completed by cDNA sequencing and Edman degradation demonstrating that the mature polypeptides contain 1009 and 998 amino acid residues respectively. In addition, they contain small signal peptide sequences. Both chains show 31% identity in the N-terminal (approximately 235 residues) and C-terminal (approximately 430 residues) globular domains which are connected by a triple helical segment (335-336 residues). Internal alignment of the globular sequences indicates a repetitive 200-residue structure (15-23% identity) occurring three times (N1, C1, C2) in each chain. These repeating subdomains are connected to each other and to the triple helix by short (15-30 residues) cysteine-rich segments. The globular domains possess several N-glycosylation sites but no cell-binding RGD sequences, which are exclusively found in the triple helical segment. Sequencing of alpha 2(VI) cDNA clones revealed two variant chains with a distinct C2 subdomain and 3' non-coding region. The repetitive segments C1, C2 and, to a lesser extent, N1 show significant identity (15-18%) to the collagen-binding A domains of von Willebrand factor (vWF) and they are also similar to some integrin receptors, complement components and a cartilage matrix protein. Since the globular domains of collagen VI come into close contact with triple helical segments during the formation of tissue microfibrils it suggests that the globular domains bind to collagenous structures in a manner similar to the binding of vWF to collagen I.

Amino Acid Sequence↗
PubMed1989

Human nidogen: complete amino acid sequence and structural domains deduced from cDNAs, and evidence for polymorphism of the gene.

Nidogen, a multifunctional glycoprotein, is an integral part of all basement membranes. In this study, human nidogen cDNAs were isolated and characterized from human placental and skin fibroblast cDNA libraries by hybridization with a mouse nidogen cDNA probe. Six overlapping clones covering 4.9 kb were characterized. The composite cDNA contained a 3,741-nucleotide open reading frame which coded for a 1,247-amino-acid peptide that included a hydrophobic signal sequence. The deduced amino acid sequence contains seven epidermal growth factor-like cysteine-rich repeats, one possible tyrosine O-sulfation site, and a possible N-glycosylation site. The tripeptide sequence -Arg-Gly-Asp- (RGD), a potential cell attachment site, was also present. Human and mouse nidogen sequences were 84% homologous at the nucleotide level and 85% homologous at the deduced amino acid level. Southern blotting of human leukocyte DNA from 23 individuals indicated that nidogen probably is a single-copy gene and shows multiple restriction fragment length polymorphisms when cleaved with Eco RI, Pvu II, Taq I, and Msp I. In particular, digestions with Pvu II revealed polymorphism in four discrete DNA fragments, which could be discriminated by hybridizations with nidogen subclones. One of the polymorphisms revealed an allelic frequency of 0.52/0.48. Thus, human nidogen gene displays RFLPs which provide analytical tools to establish genetic linkage between the nidogen gene and a clinical phenotype.

Amino Acid Sequence↗
PubMed1989

Locomotory competence and laminin-specific cell surface binding sites are lost during myoblast differentiation.

The specific interaction of embryonal cells with the extracellular matrix (ECM) is one of the principal forces influencing embryonal development (Hay, 1984; Trinkaus, 1984). We used a muscle satellite cell line (MM14dy) to determine the relationship between locomotory response to laminin and the expression of specific cell surface binding sites for it. Time lapse videomicroscopic analysis was used to study the locomotory response and radioligand binding assays and cell attachment assays were used to follow the expression levels of binding sites for laminin and its subfragments E8 and E1-4. We report here the novel finding that the ability of MM14dy to locomote over laminin diminishes and finally vanishes as the cells differentiate. The simultaneous drop in expression of binding sites for laminin is interpreted as being of potential significance during development and repair.

Animals↗
PubMed1989

Human laminin: cloning and sequence analysis of cDNAs encoding A, B1 and B2 chains, and expression of the corresponding genes in human skin and cultured cells.

A human placental lambdagt11 expression cDNA library was probed for laminin cDNAs by a combination of immunoscreening using polyclonal anti-human laminin antibody, and plaque hybridizations using a mouse laminin A chain cDNA. A total of 36 recombinant clones were isolated and characterized. Northern blot hybridizations with poly(A)+RNA, isolated from cultured human skin fibroblasts, revealed hybridization either to (a) a single 10 kb transcript consistent with A chain; (b) a single 5.7 kb transcript consistent with B1 chain; or (c) polymorphic 5.6 and 8.2 kb transcripts consistent with B2 chain of human laminin. Nucleotide sequencing of representative cDNA clones (approximately 2.5 kb in size) confirmed that these three groups of cDNAs encoded C-terminal sequences of laminin A, B1 and B2 chains, respectively. Deduced amino acid sequences for both B1 and B2 chains contained epidermal growth factor-like sequences and alpha-helical heptad repeats, as found previously for mouse laminin. Partial laminin A chain cDNA encoded 680 amino acid residues characterized by several internal repeats. This portion of the peptide accounted for a large part of the globular domain (fragment 3), the whole length of a second (T2) and portions of a third (T1) globular domain. The human A chain also contained an Arg-Gly-Asp sequence, a potential cell-binding site, which is not found in the same segment of mouse laminin. The newly isolated cDNAs were also utilized to analyze expression of laminin mRNAs by cultured human cells and tissues. The results demonstrated that the laminin A, B1, and B2 chain genes were expressed in an uncoordinate manner in both cultured cells and tissues, with a particularly low level of the A chain mRNA being present.

Amino Acid Sequence↗
PubMed1988

Amino acid sequence of the triple-helical domain of human collagen type VI.

The complete amino acid sequence of the triple-helical domain of human collagen VI was deduced from sequences of appropriate cDNA clones and confirmed to about 50% by Edman degradation of tryptic peptides. This domain consists of three different peptide segments containing some 335-336 amino acid residues originating from central portions of the alpha 1 (VI), alpha 2(VI), and alpha 3(VI) chains, respectively. Sequence identity in the X/Y positions of the Gly-X-Y repeats is rather low (10-15%) between the chains. Peculiar features of these sequences include 3 cysteine residues about 50 (alpha 3(VI)) and 89 (alpha 1(VI), alpha 2(VI)) residues away from the N-terminus and several Gly-X-Y interruptions clustered in the C-terminal two-thirds of the triple helix. These structures are presumably required for cross-linking collagen VI oligomers and for super-coiling of triple helices in the dimers. Other features include 11 Arg-Gly-Asp sequences, some of which are likely to be used as cell-binding sites, and four Asn-X-Thr sequences, allowing N-linked glycosylation along the triple helix. Junctional areas close to the helix contain short, cysteine-rich segments which may seal the triple-helical domain through disulfide bond formation, endowing it with high stability. These features, together with a low sequence homology to fiber-forming and basement-membrane collagens, document the unique character of collagen VI, whose triple helix is specifically adjusted for forming microfibrils in tissues.

Amino Acid Sequence↗
PubMed1988

Characterization of proteolytic fragments of the laminin-nidogen complex and their activity in ligand-binding assays.

Some 12 new nidogen and laminin fragments were purified from elastase, thrombin and trypsin digests and characterized by their sizes (22 kDa to greater than 300 kDa), subunit patterns on electrophoresis, partial amino acid sequences, content of specific epitopes and their binding to laminin or nidogen structures in radioligand assays. This permitted the various fragments to be ordered along the dumbbell-shaped structure of nidogen and to compare them with previously described nidogen fragments arising by endogenous proteolysis. Two nidogen fragments (E-50, E-90; 50 kDa and 90 kDa) remain associated with a large laminin fragment in elastase digests of the complex and could be dissociated with 2 M guanidine.HCl. Recombination studies demonstrated Kd = 10-20 nM for this interaction. Nidogen fragments devoid of binding activity included the tryptic peptide T-40 (40 kDa) corresponding to the rod-like domain and several larger fragments extending more to the N-terminus of nidogen. An N-terminal thrombin fragment of about 50 kDa was also inactive. Together the data show a lack of laminin binding to the N-terminal globule and rod of nidogen and provide indirect evidence that this activity is located within or close to its C-terminal globular domain. Nidogen-binding structures of laminin were obtained as two large fragments (greater than 300 kDa), P1X and E1X. They correspond to the short arm structure of laminin with one (E1X) or two (P1X) arms decreased in size to the inner rod-like segment. Shortening in E1X is mainly due to the B1 chain segment including the central globular domain which was identified as a new laminin fragment E10. Binding of E1X and P1X to nidogen was comparable to that of laminin while much lower activity was found for other laminin fragments. A 10-fold lower binding potential was also observed for the laminin-nidogen complex whose structure can now be defined in more precise molecular terms.

Amino Acid Sequence↗
PubMed1988

Laminin, a multidomain protein. The A chain has a unique globular domain and homology with the basement membrane proteoglycan and the laminin B chains.

Laminin (Mr = 800,000) is a glycoprotein consisting of three chains, A, B1, and B2, and has diverse biological activities. Previously we reported the complete primary structure of the B1 and B2 chains of mouse laminin deduced from cDNA sequence (Sasaki, M., Kohno, K., Kato, S., Martin, G. R., and Yamada, Y. (1987) Proc. Natl. Acad. Sci. U.S.A. 84, 935-939; Sasaki, M., and Yamada, Y. (1988) J. Biol. Chem. 262, 17111-17117). Here we describe the isolation, characterization, and sequence of cDNA clones spanning 9,520 bases which encode the entire A chain of mouse laminin. The nucleotide sequence of the clones contains an open reading frame of 3,084 amino acids including 24 amino acids of a signal peptide. The A chain contains some eight distinct domains including alpha-helices, cysteine-rich repeats and globules. There is considerable sequence and structural homology between the A chain and the B1 and B2 chains. However, the A chain has a unique globular structure containing homologous repeats at the carboxyl terminus and constituting one third of the molecular mass of the chain. Furthermore, the A chain contains three globules and three cysteine-rich domains at the amino terminus, whereas the B1 and B2 chains have only two each of such domains. The A chain shows homology to the basement membrane heparan sulfate proteoglycan core protein and the extracellular domain of the Drosophila neurogenic protein Notch. There is an RGD (Arg-Gly-Asp) sequence in one of the cysteine-rich domains of the A chain. This potential cell binding sequence could be active as another adhesion signal in addition to the previously identified cell binding sequence YIGSR (Tyr-Ile-Gly-Ser-Arg) of the B1 chain.

Amino Acid Sequence↗