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J H Fessler

Publications and source records attributed to J H Fessler.

At least 37 records · Page 2Linked to original sources
PubMed1990

Glutactin, a novel Drosophila basement membrane-related glycoprotein with sequence similarity to serine esterases.

Glutactin, a new acidic sulfated glycoprotein, was isolated from Drosophila Kc cell culture media. Immunofluorescence microscopy located it to embryonic basement membranes, particularly to the sequentially invaginated envelope of the central nervous system, muscle apodemes and dorsal median cell processes. Its chromosome locus is 29D. The nucleic acid sequence coding for the 1023 residue long polypeptide contains one intron and was confirmed by partial amino acid sequencing. Glutactin has a signal peptide and an amino domain of greater than 500 residues that strongly resembles acetylcholine esterases and other serine esterases, but lacks the catalytically critical serine residue. The amino and carboxyl domains of glutactin are separated by 13 contiguous threonine residues. Glutamine and glutamic acid make up 44% of glutactin's very acidic carboxyl domain. Glutactin preferentially binds Ca2+ in the presence of excess Mg2+ and four of its tyrosines are O-sulfated. Several similarities with mammalian entactin caused our previous, preliminary mention of glutactin as a putative Drosophila entactin, but sequence comparison now shows them to be different proteins.

Amino Acid Sequence↗
PubMed1988

Drosophila basement membrane procollagen alpha 1(IV). II. Complete cDNA sequence, genomic structure, and general implications for supramolecular assemblies.

A Drosophila melanogaster gene for a basement membrane procollagen chain was recently identified from the sequence homology of the carboxyl (NC1) end of the polypeptide that it encodes with the corresponding domain of human and murine collagens IV (Blumberg, B., MacKrell, A. J., Olson, P. F., Kurkinen, M., Monson, J. M., Natzle, J. E., and Fessler, J. H. (1987) J. Biol. Chem. 262, 5947-5950). This gene is at chromosome location 25C. Here we report the complete 6-kilobase cDNA sequence coding for a chain of 1775 amino acids, as well as the genomic structure. The gene is composed of nine relatively large exons separated by eight relatively small introns. This organization is different from the multiple small exons separated by large introns reported for mouse and human type IV collagens (Kurkinen, M., Bernard, M. P., Barlow, D. P., and Chow, L. T. (1985) Nature 317, 177-179. Sakurai, Y., Sullivan, M., and Yamada, Y. (1986) J. Biol. Chem. 261, 6654-6657. Soininen, R., Tikka, L., Chow, L., Pihlajaniemi, T., Kurkinen, M., Prockop, D. J., Boyd, C. D., and Tryggvason, K. (1986) Proc. Natl. Acad. Sci. U.S.A. 83, 1568-1572). Drosophila and human alpha 1(IV) procollagen chains share not only polypeptide domains near their amino and carboxyl ends for making specialized, intermolecular junctional complexes, but also 11 of 21 sites of imperfections of the collagen triple helix. However, neither the number nor the nature of the amino acids in these imperfections appear to have been conserved. These imperfections of the helical sequence may be important for the supramolecular assembly of basement membrane collagen. The 9 cysteine residues of the Drosophila collagen thread domain are arranged as several variations of a motif found in vertebrate collagens IV only near their amino ends, in their "7 S" junctional domains. The relative positions of these cysteine residues provide numerous opportunities for disulfide bonding between molecules in both parallel and antiparallel arrays. There is a pseudorepeat of one-third of the thread length, and there are numerous possibilities for disulfide-linked microfibrils and networks. We propose that collagen microfibrils, stabilized by disulfide segment junctions, are a versatile ancestral form from which specialized collagen fibers and networks arose.

Amino Acid Sequence↗
PubMed1988

Drosophila basement membrane procollagen IV. I. Protein characterization and distribution.

A collagen was isolated from Drosophila E85, Schneider line 2L and Kc cell cultures. The purified protein was characterized and antibodies were raised against it. Immunofluorescence microscopy locates this material to the regions of basement membranes of Drosophila embryos, larvae, and adults. The molecules are mostly, or entirely, homotrimers of one polypeptide chain linked by interchain disulfide bonds. The partial amino acid sequences of a cyanogen bromide cleavage product of this chain are identical with a part of the virtual translation product of the Drosophila pro alpha 1(IV) nucleotide sequence that is reported in the accompanying paper. This gene is at Drosophila chromosome location 25C and was identified by the high homology of one part of it with the noncollagenous carboxyl terminus (NC1) of vertebrate type IV basement membrane collagens (Blumberg, B., MacKrell, A. J., Olson, P. F., Kurkinen, M., Monson, J. M., Natzle, J. E., and Fessler, J. H. (1987) J. Biol. Chem. 262, 5947-5950). In the electron microscope each molecule appears as a thread with a knob at one end, which contains the carboxyl peptide domains. The variation of flexibility of the thread was mapped along its length. Pulse-chase labeling of cell cultures showed that these molecules associate into disulfide-linked dimers and higher oligomers that can be partly separated by velocity sedimentation and are resolved by sodium dodecyl sulfate-agarose gel electrophoresis. Dimers and higher oligomers formed by overlap of the amino ends of molecules were found. Mild pepsin digestion of Drosophila embryos and larvae solubilized the corresponding disulfide-linked collagen molecules, and Staphylococcus aureus V8 protease peptide maps showed the identity of the collagen derived from animals and from cell cultures. Individual, native molecules have a sedimentation coefficient s20,w = 4.1 S, the dichroic spectrum and amino acid composition of a collagen, and a Tm = 31 degrees C. Positive in situ hybridization with a specific probe for this collagen began 6-8 h after egg laying and showed message in the locations of embryos and larvae which reacted with the antibodies. This included some prominent individual cells in the hemolymph.

Amino Acids↗
PubMed1988

Reductive cleavage and reformation of the interchain and intrachain disulfide bonds in the globular hexameric domain NC1 involved in network assembly of basement membrane collagen (type IV).

The formation of collagen IV dimers in the extracellular space requires the association of two C-terminal globular domains giving rise to a large hexameric structure NC1 (Mr = 170,000). NC1 hexamer was purified from collagenase digests of a mouse tumor and several human tissues. It was shown by electrophoresis to consist of two kinds of cross-linked, dimeric segments, Da and Db (Mr about 50,000), and monomeric segments in a molar ratio of about 3:1. In the native hexamers free SH groups were detectable by N-[14C]ethylmaleimide and other sulfhydryl reagents. They account for 4-11% of the total number of cysteine residues with some variations between preparations from different sources and in the distribution between monomers and dimers. Reduction with 10 mM dithioerythritol under non-denaturing condition completely converted dimers into monomers and allowed the alkylation of all twelve cysteine residues present in each monomeric NC1 segment. A monomeric intermediate with four to six free SH groups and a higher electrophoretic mobility than the final product was observed. Generation of this intermediate from dimers Da and Db follows apparently different routes proceeding either directly or through a dimeric intermediate respectively. The time course of conversion is best described by a mechanism consisting of two (Db) or three (Da) consecutive steps with pseudo-first-order rate constants ranging from 0.14 ms-1 to 0.5 ms-1. Glutathione-catalyzed reoxidation of completely reduced NC1 in the presence of 2 M urea results in a product indistinguishable from native material by ultracentrifugation and electrophoresis pattern. The data suggest that in situ formation of NC1 structures is catalyzed by a small fraction (5-10%) of intrinsic SH groups leading to the formation and stabilization of dimers by rearrangement of disulfide bonds.

Animals↗
PubMed1988

The lethal myospheroid gene of Drosophila encodes a membrane protein homologous to vertebrate integrin beta subunits.

A mutant of Drosophila melanogaster carrying the lethal(1) myospheroid mutation [l(1)mys] has a defective musculature and a phenotype that suggests a defect of basement membranes. The genomic region that is interrupted by an insertion in a mutant carrying l(1)mys was used to isolate cDNA clones, and their sequences are presented here. The cDNA sequence predicts a cysteine-rich integral membrane protein that displays 45% sequence identity to chicken integrin and the human fibronectin receptor beta subunit and much greater similarity over localized segments. These similarities extend to other vertebrate integrin beta subunits, and we conclude that the myospheroid protein is an integrin beta subunit of Drosophila. This implies evolutionary conservation of a group of transmembrane proteins that are receptors for extracellular matrix and, coupled with the myospheroid phenotype, indicates an important role for the interaction of cells with extracellular matrix during development.

Amino Acid Sequence↗
PubMed1987

Papilin: a Drosophila proteoglycan-like sulfated glycoprotein from basement membranes.

A sulfated glycoprotein was isolated from the culture media of Drosophila Kc cells and named papilin. Affinity purified antibodies against this protein localized it primarily to the basement membranes of embryos. The antibodies cross-reacted with another material which was not sulfated and appeared to be the core protein of papilin, which is proteoglycan-like. After reduction, papilin electrophoresed in sodium dodecyl sulfate-polyacrylamide gel electrophoresis as a broad band of about 900,000 apparent molecular weight and the core protein as a narrow band of approximately 400,000. The core protein was formed by some cell lines and by other cells on incubation with 1 mM 4-methylumbelliferyl xyloside, which inhibited formation of the proteoglycan-like form. The buoyant density of papilin in CsCl/4 M guanidine hydrochloride is 1.4 g/ml, that of the core protein is much less. Papilin forms oligomers linked by disulfide bridges, as shown by sodium dodecyl sulfate-agarose gel electrophoresis and electron microscopy. The protomer is a 225 +/- 15-nm thread which is disulfide-linked into a loop with fine, protruding thread ends. Oligomers form clover-leaf-like structures. The protein contains 22% combined serine and threonine residues and 25% combined aspartic and glutamic residues. 10 g of polypeptide has attached 6.4 g of glucosamine, 3.1 g of galactosamine, 6.1 g of uronic acid, and 2.7 g of neutral sugars. There are about 80 O-linked carbohydrate chains/core protein molecule. Sulfate is attached to these chains. The O-linkage is through an unidentified neutral sugar. Papilin is largely resistant to common glycosidases and several proteases. The degree of sulfation varies with the sulfate concentration of the incubation medium. This proteoglycan-like glycoprotein differs substantially from corresponding proteoglycans found in vertebrate basement membranes, in contrast to Drosophila basement membrane laminin and collagen IV which have been conserved evolutionarily.

Amino Acids↗
PubMed1987

Basement membrane procollagen IV and its specialized carboxyl domain are conserved in Drosophila, mouse, and human.

Interaction with the extracellular matrix is important for the proliferation and differentiation of cells during development. A specialized extracellular matrix, basement membrane, is built around a scaffold of procollagen IV molecules. We report the sequence of a 2.5-kilobase cDNA which contains the carboxyl end of a Drosophila melanogaster procollagen IV. The amino acid sequence of the carboxyl-terminal domain, which forms an essential intermolecular linkage between procollagen IV molecules, is 59% identical in Drosophila and vertebrate procollagens IV, and an additional 17% of residues are conservatively substituted. This implies that the nature of the linkage is also conserved. We suggest that intermolecular junctions through procollagen IV carboxyl domains are fundamental elements of the molecular architecture of Metazoan basement membranes and have been conserved during evolution. The isolation and identification of this basement membrane collagen gene of Drosophila will help in deducing the function of procollagen IV in basement membranes.

Amino Acid Sequence↗
PubMed1987

Drosophila laminin: characterization and localization.

Drosophila laminin was isolated from the medium of Drosophila Kc cell cultures. It was purified by velocity sedimentation, gel filtration, and chromatography. Drosophila laminin is a disulfide-linked molecule consisting of three chains with apparent molecular masses of 400, 215, and 185 kD. In electron micrographs, it has the cross-shaped appearance with globular domains characteristic of vertebrate laminin with closely similar dimensions. The amino acid composition and lectin-binding properties of Drosophila laminin are given. Polyclonal antibodies to Drosophila laminin were prepared and their specificity was established. In developing embryos immunofluorescence staining was detected between 6 and 8 h of development; and in sections of 8-9-h and older embryos immunostaining was seen at sites where basement membranes are present surrounding internal organs, muscles, underlying the hypodermal epithelium, and in the nervous system. Basement membrane staining was also seen in larva and adults. Cells from Drosophila embryos dissociated at the cellular blastoderm stage were grown in culture and some specific, differentiated cells synthesized laminin after several hours of culture as shown by immunofluorescence. The significance of the evolutionary conservation of the structure of this basement membrane component is discussed.

Amino Acids↗
PubMed1986

Intracellular transport and tyrosine sulfation of procollagens V.

Several tyrosine residues of the extracellular p-collagens V and collagens V are sulfated [Fessler, L. I., Brosh, S., Chapin, S. and Fessler, J. H. (1986) J. Biol. Chem. 261, 5034-5040]. Here, the sulfation of their intracellular precursors, the procollagens V, was studied. A Golgi-enriched subcellular fraction of chick embryo tendon catalyzed the sulfation of tyrosine residues in both endogenous and added, unsulfated procollagens V with the sulfate donor 3'-phosphoadenosine 5'-[35S]phosphosulfate. Intracellular tyrosine sulfation of procollagen V occurred at a point distal to the cis Golgi compartment as judged by change of the N-linked carbohydrate of procollagen V from being endoglycosidase-H-sensitive to being resistant. The time course of the intracellular modifications of procollagen V was determined by incubating tendons with 3H-labeled amino acids and with [35S]sulfate. The pro alpha(V) chains were synthesised in about 10 min and then assembled into unsulfated procollagen V molecules. Tyrosine sulfation occurred 50 min after completion of polypeptide synthesis and the molecules were successively sulfated in the order in which they had been synthesized. The antimicrotubular drug Nocodazole, which disrupts the spatial organization of the Golgi, decreased the time interval between synthesis of procollagens V and sulfation. The sulfated procollagens V were soon secreted and cut to sulfated p-collagens V. Sulfated pro alpha 1(V) chains were cleaved faster than sulfated pro alpha 1'(V) chains. The relationship of sequential protein modification to spatial cellular organization is discussed.

Animals↗
PubMed1986

Folding of carboxyl domain and assembly of procollagen I.

An early form of procollagen I was found in acetic acid extracts of radioactively labeled chick embryo skull bones. It resembled native procollagen I, but sedimented slightly faster, and its component chains were slightly underhydroxylated and were not disulfide-linked to each other, although its propeptides were internally disulfide-bonded. Pulse-chase experiments showed its conversion to disulfide-linked procollagen. As the same conversion occurred when proline hydroxylation was blocked by 2,2'-dipyridyl, we infer that the formation of this precursor from its component chains does not require collagen triple helix formation. We suggest that interaction between the folded carboxyl propeptides of individual pro-alpha (I) chains is an important step in the formation of this precursor and of procollagen I. Studies of the refolding and association of fully reduced and denatured carboxyl propeptides supported this concept. In the presence of glutathione the correct disulfide bonds could be reestablished, as judged by a mapping of some tryptic peptides. Individual carboxyl propeptides refolded first, and this occurred even in 2 M urea. Recognition between folded carboxyl propeptides occurred only when less than 0.5 M urea was present. The presence of the carboxyl telopeptides was important for trimeric reassembly. Individual propeptides also folded spontaneously during cell-free translation of pro-alpha (I) chains and were recognized by specific antibodies. We consider the role of carboxyl propeptides in the formation of procollagen I molecules and suggest a model of self-assembly, possibly facilitated by interactions with the luminal surface of the rough endoplasmic reticulum.

Animals↗
PubMed1986

Tyrosine sulfation in precursors of collagen V.

Radioactive labeling of p-collagens V, collagens V, and, to a small extent, of procollagen V occurred when [35S]sulfate was incubated with tendons or primary tendon cell cultures, or blood vessels and crops of 17- to 19-day-old chick embryos, or with lung slices from neonatal rats. Most or all of this label is in the form of 1 or more sulfated tyrosine residues/chain of p alpha 1(V), alpha 1(V), p alpha 1'(V), alpha 1'(V), p alpha 2(V), and alpha 2(V), and it remains attached through purification by dialysis, ammonium sulfate precipitation, CsCl-GdnCl2 equilibrium buoyant density and velocity sedimentations, ion-exchange chromatography, and sodium dodecyl sulfate gel electrophoresis. Radioactive tyrosine sulfate was identified in alkaline hydrolysates of these collagen V chains, after labeling the tissues with either [35S]sulfate or [3H]tyrosine, by electrophoretic and chromatographic comigration with a tyrosine sulfate standard. Tunicamycin A1, which inhibits the attachment of N-linked complex carbohydrate, did not interfere with the sulfation process. The tyrosine sulfate is located in a noncollagenous domain, which is probably adjacent to the amino end of the collagen helix, and is retained throughout the physiological proteolytic processing of procollagens V. After digestion with Staphylococcus aureus V8 protease, 35S-labeled p alpha 1(V) and alpha 1(V) chains gave the same map of labeled peptides, and this differed from the map given by p alpha 1'(V) and alpha 1'(V) chains. Little sulfation of p alpha 2(V) and alpha 2(V) chains occurs. The implications of these observations for the structure and properties of procollagens V and their derivatives are considered.

Animals↗
PubMed1986

Biosynthesis and supramolecular assembly of procollagen IV in neonatal lung.

The rate of biosynthesis of procollagen IV, the principal collagen of basement membranes, and the concentration of specific RNAs coding for procollagen IV were measured in neonatal rat lungs. Both decreased sharply at birth and then recovered again a few days later. The supramolecular assembly of procollagen IV was followed in neonatal rat, mouse, and chick lungs, which actively elaborate endothelial and alveolar basement membranes, and in chick embryo gizzard which is rich in smooth muscle. The tetramer of four procollagen IV molecules linked covalently through their amino ends was isolated as an assembly intermediate from all these tissues. While noncovalent association of the carboxyl ends of two procollagen IV molecules occurred readily, the subsequent establishment of covalent cross-links was substantially slower in the junctional complexes of the carboxyl ends than of the amino ends. Both disulfide bonds and other, unidentified covalent links formed. The six component carboxyl peptides of a junctional complex became progressively covalently linked into two kinds of carboxyl peptide pairs. We conclude that both amino-linked tetramers and carboxyl-linked dimers of procollagen IV molecules are intermediates in the biological assembly of the collagen networks of these basement membranes.

Age Factors↗
PubMed1985

Isolation of a new procollagen V chain from chick embryo tendon.

Whole tendons of chick embryos synthesize procollagens V which consist of three pro-alpha chains: pro-alpha 1'(V), pro-alpha 1(V) and pro-alpha 2(V). This report shows that while the pro-alpha 1'(V) chain is similar to the pro-alpha 1(V) chain in many respects, such as similar but not identical peptide maps, it also distinctly differs from it in size and in other ways. The new chain is denoted as pro-alpha 1' to indicate the relationship. We have failed to see conversion of one chain into the other and they are regarded as variants, although we do not know whether they are different transcripts of one gene or products of two closely related genes. The pro-alpha(V) chains are assembled into the disulfide-linked homotrimer (pro-alpha 1'(V))3 and the heterotrimer [(pro-alpha 1'(V)S-S-pro-alpha 2(V))pro-alpha 1(V)] and a smaller amount of [(pro-alpha 1(V)2pro-alpha 2(V)]. The pro-alpha 1'(V) chains are processed similarly to the pro-alpha 1(V) by the initial removal of the presumed carboxyl propeptide yielding p-alpha 1'(V) and then by reduction in the size of the noncollagenous, presumed amino propeptide to yield alpha 1'(V). A size difference between the alpha 1'(V) and alpha 1(V) series of molecules is demonstrated by velocity sedimentation and by electrophoretic mobility of the reduced molecules. This difference is ascribed to a difference in the size of the propeptides because after pepsin digestion the products of both series of molecules are the same size and electrophorese like alpha 1(V)(pepsin). The carboxyl propeptides of pro-alpha 1(V) and pro-alpha 1'(V) are the same size, but the amino propeptide of pro-alpha 1'(V) is smaller than that of pro-alpha 1(V). The amino propeptide of pro-alpha 1'(V) and p-alpha 1'(V) also lacks asparagine-linked complex carbohydrate, which is linked to propeptides of the p-alpha 1(V) and p-alpha 2(V) chains. Differences between the alpha 1(V) and alpha 1'(V) series of molecules remain in material synthesized in the presence of tunicamycin. Primary cultures of tendon cells synthesize procollagen V consisting of the above three chains, but the procollagen V made by cultured tendon sheath synovial cells predominantly contains [(pro-alpha 1(V))2pro-alpha 2(V)].

Animals↗
PubMed1985

Biosynthesis of collagen.

During the biosynthesis and assembly of collagen structures, disulfide links can serve several functions. During biosynthesis they successively stabilize intrapeptide folding and associations of three chains into one molecule. Studies on the refolding and reassociation of reduced and denatured carboxyl propeptides of procollagen I showed that successive interactions of folding and assembly are successively weaker. Disulfide bridges were reestablished within correctly refolded carboxyl propeptides. Rearrangements of disulfide bridges may occur during the processing of type V procollagen molecules as these collagens become incorporated into extracellular matrix. The basement membrane procollagen IV molecules become disulfide linked at each end into networks, and there are indications that further rearrangements of disulfide links may allow additional modulation.

Animals↗
PubMed1984

Characterization of the procollagen IV cleavage products produced by a specific tumor collagenase.

The specific mammalian collagenase isolated from cultures of metastatic mouse PMT sarcoma cells cleaves murine procollagen IV into two segments, of approximate mass ratio 3:1. These fragments were separated by velocity sedimentation, visualized by electron microscopy, and analyzed. The longer COOH-terminal procollagen segment has a 270-nm collagenous portion with a knob at one end. This knob consists of the three previously identified, noncollagenous carboxyl propeptides, of approximately 30,000 daltons each. These carboxyl propeptides are chain-specific, and the three chains of each segment have the same amino to carboxyl orientation. The collagenase cuts through all three chains at one site, and the three-component chains of both the longer COOH-terminal procollagen segment and the shorter NH2-terminal procollagen segment are linked by interchain disulfide bridges. The enzyme cuts off the same COOH-terminal procollagen segment from procollagen IV monomers and tetramers, and the flexibility of this segment is similar to that of interstitial collagen helices. The amino ends of the NH2-terminal procollagen segments derived from tetramers remain joined as the 32-nm long "7 S collagen" junctional complex, and the remaining 89-nm long projecting threads are significantly more flexible than the COOH-terminal procollagen segment. The electrophoretic mobilities of the enzyme cleavage products are consistent with a heterotrimeric composition of this procollagen IV.

Amino Acid Sequence↗
PubMed1984

Silk--a new substrate for UDP-d-xylose:proteoglycan core protein beta-D-xylosyltransferase.

The formation of most connective tissue polysaccharides is initiated by transfer of D-xylose from UDP-D-xylose to specific serine residues in the core proteins of the putative proteoglycans. The substrate specificity of the xylosyltransferase catalyzing this reaction has not yet been examined in detail, but it appears that a -Ser-Gly- pair is an essential part of the substrate structure. Since the preparation of the known acceptors (e.g., Smith-degraded or HF-treated cartilage proteoglycan) involves a substantial effort, we have searched for readily available proteins with the -Ser-Gly-sequence, which might serve as alternative substrates. In the present work, it was found that silk fibroin from Bombyx mori, which consists, in large part, of the repeating hexapeptide, Ser-Gly-Ala-Gly-Ala-Gly, is an excellent substrate for the xylosyltransferase from embryonic chick cartilage. Pieces of silk were used directly in the reaction mixtures, and [14C]xylose transferred from UDP-D-[14C]xylose was measured by liquid scintillation spectrometry after rinsing the silk in 1 M NaCl and water. Substantially greater incorporation was observed with preparations of silk or fibroin which had been dissolved in 60% LiSCN and subsequently dialyzed exhaustively or diluted appropriately. Under standard reaction conditions, the Vmax for fibroin was 531 pmol/h/mg enzyme protein, as compared to 223 pmol/h/mg for Smith-degraded proteoglycan. Km values were 182 mg/liter (fibroin) and 143 mg/liter (Smith-degraded proteoglycan). The product of [14C]xylose transfer to silk was alkali labile, and [14C]xylitol was formed when [14C]xylosylsilk was treated with borohydride in alkali. Proteolytic digestion with papain, Pronase, leucine aminopeptidase, and carboxypeptidase A yielded a radioactive product which was identified as [14C]xylosylserine by electrophoresis and chromatography. The identity of the isolated [14C]xylosylserine was further supported by its resistance to treatment with alkali (0.5 M KOH; 100 degrees C; 8 h) and by acid hydrolysis which yielded [14C]xylose. Tryptic and chymotryptic fragments from fibroin were also good xylose acceptors and had Vmax values 60-70% of that observed for the intact protein. Substantial acceptor activity was displayed also by the sericin fraction of silk and by the silk sequence hexapeptide. Ser-Gly-Ala-Gly-Ala-Gly; the latter had a Vmax value close to 20% of that of intact fibroin.

Amino Acid Sequence↗