Amino acid sequence of mouse nidogen, a multidomain basement membrane protein with binding activity for laminin, collagen IV and cells. EMBO J 8: 65-72 (original) (raw)
Related papers
Binding of nidogen and the laminin-nidogen complex to basement membrane collagen type IV
European Journal of Biochemistry, 1989
The laminin-nidogen complex and purified nidogen both bind collagen IV but not other collagens, as shown by solid-state ligand-binding and inhibition assays. Laminin purified from the dissociated complex and a variety of laminin proteolytic fragments failed to bind collagen IV. Complexes formed in solution between nidogen or laminin-nidogen and collagen IV were visualized by rotary shadowing which identified one major binding site about 80 nm away from the C-terminus of the collagen triple helix. A second, weaker binding site may exist closer to its N-terminus. Binding sites of nidogen were assigned to its C-terminal globular domain which also possesses laminin-binding structures. A more diverse collagen-IV-binding pattern was observed for the laminin-nidogen complex, whereby interactions may involve both nidogen and short-arm structures of laminin.
The EMBO Journal, 1989
The whole amino acid sequence of nidogen was deduced from cDNA clones isolated from expression libraries and confirmed to-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 3hydroxylation, 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 laminiin and collagen IV are present on the C-terminal globule but not yet precisely localized.
The EMBO journal, 1991
Recombinant mouse nidogen and two fragments were produced in mammalian cells and purified from culture medium without resorting to denaturing conditions. The truncated products were fragments Nd-I (positions 1-905) comprising the N-terminal globule and rod-like domain and Nd-II corresponding mainly to the C-terminal globule (position 906-1217). Recombinant nidogen was indistinguishable from authentic nidogen obtained by guanidine dissociation from tumor tissue with respect to size, N-terminal sequence, CD spectra and immunochemical properties. They differed in protease stability and shape indicating that the N-terminal domain of the more native, recombinant protein consists of two globules connected by a flexible segment. This established a new model for the shape of nidogen consisting of three globes of variable mass (31-56 kDa) connected by either a rod-like or a thin segment. Recombinant nidogen formed stable complexes (Kd less than or equal to 1 nM) with laminin and collagen IV ...
European Journal of Biochemistry, 1992
A large, low-density form of heparan sulfate proteoglycan was isolated from the Engelbreth-Holm-Swarm (EHS) tumor and demonstrated to bind in immobilized-ligand assays to laminin fragment E3, collagen type IV, fibronectin and nidogen. The first three ligands mainly recognize the heparan sulfate chains, as shown by inhibition with heparin and heparan sulfate and by the failure to bind to the proteoglycan protein core. Nidogen, obtained from the EHS tumor or in recombinant form, binds exclusively to the protein core in a heparin-insensitive manner. Studies with other laminin fragments indicate that the fragment E3 possesses a unique binding site of laminin for the proteoglycan. A major binding site of nidogen was localized to its central globular domain G2 by using overlapping fragments. This allows for the formation of ternary complexes between laminin, nidogen and proteoglycan, suggesting a key role for nidogen in basement-membrane assembly.
Nidogen mediates the formation of ternary complexes of basement membrane components
Kidney International, 1993
Nidogen mediates the formation of ternary complexes of basement membrane components. Using a recombinant nidogen we have probed the calcium binding potential of various nidogen domains, examined the binding of nidogen to various basement membrane proteins and assessed the ability of nidogen to mediate the formation of ternary complexes between laminin and heparan sulfate proteoglycan and collagen IV and laminin. The results of these experiments indicate that the Ca2 binding is on the rod-like domain with additional binding observed on the N-terminal Gi domain. With regard to the role of nidogen in mediating complex formation among basement membrane components it was demonstrated that nidogen effectively promotes the formation of a ternary complex between laminin and collagen IV, with both of these components interacting independently with nidogen. Similarly, nidogen mediates a ternary complex formation between laminin and proteoglycan. Interestingly, the interaction between proteoglycan and nidogen is through the protein core of the proteoglycan.
Laboratory investigation; a journal of technical methods and pathology, 2002
Entactin-1 (nidogen-1) is an ubiquitous component of basement membranes. From in vitro experiments, entactin-1 was assigned a role in maintaining the structural integrity of the basement membrane because of its binding affinity to other components, such as type IV collagen and laminin. Entactin-1 also interacts with integrin receptors on the cell surface to mediate cell adhesion, spreading, and motility. Targeted disruption of the entactin-1 gene in the mouse presented in this study revealed a duplication of the entacin-1 locus. Homozygous mutants for the functional locus lacked entactin-1 mRNA and protein and often displayed seizure-like symptoms and loss of muscle control in the hind legs. The behavior patterns suggested the presence of neurologic deficits in the central nervous system, thus providing genetic evidence linking entactin-1 to proper functions of the neuromuscular system. In homozygous mutants, structural alterations in the basement membranes were found only in select...
Basement Membranes in Skin Are Differently Affected by Lack of Nidogen 1 and 2
Journal of Investigative Dermatology, 2008
The nidogen-laminin interaction is proposed to play a key role in basement membrane (BM) assembly. However, though there are similarities, the phenotypes in mice lacking nidogen 1 and 2 (nidogen double null) differ to those of mice lacking the nidogen binding module (␥1III4) of the laminin ␥1 chain. This indicates different cell-and tissue-specific functions for nidogens and their interaction with laminin and poses the question of whether the phenotypes in nidogen double null mice are caused by the loss of the laminin-nidogen interaction or rather by other unknown nidogen functions. To investigate this, we analyzed BMs, in particular those in the skin of mice lacking the nidogen binding module. In contrast to nidogen double null mice, all skin BMs in ␥1III4-deficient mice appeared normal. Furthermore, although nidogen 1 deposition was strongly reduced, nidogen 2 appeared unchanged. Mice with additional deletion of the laminin ␥3 chain, which contains a ␥1-like nidogen binding module, showed a further reduction of nidogen 1 in the dermoepidermal BM; however, this again did not affect nidogen 2. This demonstrates that in vivo only nidogen 1 deposition is critically dependent on the nidogen binding modules of the laminin ␥1 and ␥3 chains, whereas nidogen 2 is independently recruited either by binding to an alternative site on laminin or to other BM proteins.
Basement membranes (BMs) are thin sheet-like specialized extracellular matrices found at the basal surface of epithelia and endothelial tissues. They have been conserved across evolution and are required for proper tissue growth, organization, differentiation and maintenance. The major constituents of BMs are two independent networks of Laminin and Type IV Collagen interlinked by the proteoglycan Perlecan and the glycoprotein Nidogen/entactin (Ndg). The ability of Ndg to bind in vitro Collagen IV and Laminin, both with key functions during embryogenesis, anticipated an essential role for Ndg on morphogenesis linking the Laminin and Collagen IV networks. This was supported by results from in vitro and cultured embryonic tissues experiments. However, the fact that elimination of Ndg in C. elegans and mice did not affect survival, strongly questioned this proposed linking role. Here, we have isolated mutations in the only Ndg gene present in Drosophila. We find that while, similar to C...