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Biomedical subjects

J E Celis

Publications and source records attributed to J E Celis.

At least 19 recordsLinked to original sources

Molecular cloning and expression of a transformation-sensitive human protein containing the TPR motif and sharing identity to the stress-inducible yeast protein STI1.

A transformation-sensitive human protein (IEF SSP 3521) that is 2-fold up-regulated in SV40-transformed MRC-5 fibroblasts has been purified by two-dimensional gel electrophoresis, microsequenced, and cDNA cloned using oligodeoxyribonucleotides. The 2.1-kilobase cDNA encodes a 543-amino acid protein with a calculated molecular mass of 62.6 kDa and a calculated pI of 6.77. Expression of the cDNA in AMA cells using the vaccinia virus expression system followed by two-dimensional gel electrophoresis showed that the protein comigrated with IEF SSP 3521. The protein contains the tetratricopeptide repeat found in families of fungal proteins required for mitosis and RNA synthesis. In particular, the protein has 42% amino acid sequence identity to STI1, a stress-inducible mediator of the heat shock response in Saccharomyces cerevisiae. Northern blot analysis indicated that the 3521 mRNA is up-regulated in several transformed cells. Immunofluorescence studies using a polyclonal antibody raised against the purified protein revealed that the antigen is present mainly in the nucleus of SV40 transformed MRC-5 fibroblasts, while it localizes to the Golgi apparatus and small vesicles in their normal counterparts. The possible physiological role of IEF SSP 3521 is discussed in the light of the structural relationship with STI1.

Amino Acid Sequence

The human keratinocyte two-dimensional gel protein database (update 1992): towards an integrated approach to the study of cell proliferation, differentiation and skin diseases.

The master two-dimensional gel database of human keratinocytes currently lists 2980 cellular proteins (2098 isoelectric focusing, IEF; and 882 nonequilibrium pH gradient electrophoresis, NEPHGE) many of which correspond to posttranslational modifications. About 20% of all recorded proteins have been identified (protein name, organelle components, etc.) and they are listed in alphabetical order together with their M(r), pI, cellular localization and credit to the investigator(s) that aided in the identification. Also, we have listed 145 microsequenced proteins that are recorded in this database. As an aid in localizing the polypeptides we have included blow-ups of the master images (IEF, NEPHGE) displaying all the protein numbers. In the long run, the master keratinocyte database is expected to link protein and DNA sequencing and mapping information (Human Genome Program) and to provide an integrated picture of the expression levels and properties of the thousands of proteins that orchestrate various keratinocyte functions both in health and disease.

Cell Differentiation

Microsequences of 145 proteins recorded in the two-dimensional gel protein database of normal human epidermal keratinocytes.

Microsequencing of proteins recovered from two-dimensional (2-D) gels is being used systematically to identify proteins in the master human keratinocyte 2-D gel database. To date, about 250 protein spots recorded in human 2-D gel databases have been microsequenced and, of these, 145 are recorded in the keratinocyte database under the entry partial amino acid sequence. Coomassie Brilliant Blue-stained protein spots cut from several (up to 40) dry gels were concentrated by elution-concentration gel electrophoresis, electroblotted onto PVDF membranes and digested in situ with trypsin. Eluting peptides were separated by reversed-phase HPLC, collected individually and sequenced. Computer search using the FASTA and TFASTA programs from Genetics Computer Group indicated that 110 of the microsequenced polypeptides shared significant similarity with proteins contained in the PIR, Mipsx or GenEMBL databases. Only 35 polypeptides corresponded to hitherto unknown proteins. Peptide sequences of all 145 proteins are listed together with their coordinates (apparent molecular weight and pI) in the keratinocyte database.

Amino Acid Sequence

Workshop on two-dimensional gel protein databases.

A workshop on two-dimensional gel electrophoresis (2-DE) protein database, organized by the Committee on Data for Science and Technology (CODATA) of the International Council of Scientific Unions Task Group on Biological Macromolecules, was held at the CODATA Secretariat in Paris on March 9, 1992. Eleven scientists from eight different countries represented various aspects of 2-DE analysis--namely, cellular protein database development and protein microsequencing methodologies. The purpose of the workshop was to explore means of integrating the rapidly expanding body of information on 2-DE resolved proteins from different laboratories. A major proposal emanating from the workshop was the establishment of an intermediary or "relational" 2-DE gel protein database. This intermediary database, which would catalogue pertinent information on 2-DE resolved proteins (experimental source, 2-DE loci, biological information, etc.) could be an adjunct to, and accessed through, the existing international protein sequence databanks. It would function as a pointer for researchers to the individual 2-DE protein databases where primary and more specialized 2-DE data would be housed.

Databases, Factual

Molecular cloning and expression of a novel keratinocyte protein (psoriasis-associated fatty acid-binding protein [PA-FABP]) that is highly up-regulated in psoriatic skin and that shares similarity to fatty acid-binding proteins.

Analysis by means of two-dimensional (2D) gel electrophoresis of the protein patterns of normal and psoriatic unfractionated non-cultured keratinocytes has revealed a few low-molecular-weight proteins that are highly up-regulated in psoriatic skin. These include psoriasin; calgranulin B, also known as MRP 14, L1, or calprotectin; calgranulin A or MRP 8; and cystatin A or stefin A. Here, we have cloned and sequenced the cDNA (clone 1592) encoding a new member of this group of low-molecular-weight proteins [isoelectric focusing (IEF) SSP 3007 in the keratinocyte 2D gel protein database] that we have termed PA-FABP (psoriasis-associated fatty acid-binding protein). The deduced sequence predicted a protein with molecular weight of 15,164 daltons and a calculated pI of 6.96, values that are close to those recorded in the keratinocyte 2D gel protein database. The protein comigrated with PA-FABP as determined by 2D gel analysis of [35S]-methionine-labeled proteins expressed by transformed human amnion (AMA) cells transfected with clone 1592 using the vaccinia virus expression system and reacted with a rabbit polyclonal antibody raised against 2D gel purified PA-FABP. Structural analysis of the amino acid sequence revealed 48%, 52%, and 56% identity to known low-molecular-weight fatty acid-binding proteins belonging to the FABP family. Northern blot analysis showed that PA-FABP mRNA is indeed highly up-regulated in psoriatic keratinocytes. The transcript is present in human cell lines of epithelial and lymphoid (Molt 4) origin but cannot be detected in normal or SV40 transformed MRC-5 fibroblasts. 2D gel protein analysis of normal primary keratinocytes cultured for at least 8 d under conditions that promoted incomplete terminal differentiation [serum-free keratinocyte (SFK) medium supplemented with epidermal growth factor (EGF), pituitary extract, and 10% fetal calf serum] revealed a strong up-regulation of PA-FABP, psoriasin, calgranulins A and B, and a few other proteins that are highly expressed in psoriatic skin. The levels of these proteins exceeded by far those observed in non-cultured normal keratinocytes implying that the cultured cells have followed an altered pattern of differentiation that resembles--at least in part--that of non-cultured psoriatic keratinocytes. The implications of these results for the study of psoriasis are discussed.

Amino Acid Sequence

A fibroblast-associated antigen: characterization in fibroblasts and immunoreactivity in smooth muscle differentiated stromal cells.

Fibroblasts with smooth muscle differentiation are frequently derived from human breast tissue. Immunofluorescence cytochemistry of a fibroblast-associated antigen recognized by a monoclonal antibody (MAb), 1B10, was analyzed with a view to discriminating smooth muscle differentiated fibroblasts from vascular smooth muscle cells. The antigen was detected on the cell surface and in cathepsin D-positive and acridine orange-accumulating vesicular compartments of fibroblasts. Ultrastructurally, the antigen was revealed in coated pits and in endosomal and lysosomal structures. 1B10 recognized three major brands migrating at apparent Mr of 38,000, 45,000, and 80,000, in addition to many minor bands between Mr 45,000 and 97,000, including Mr 52,000. The Mr 45,000 and 38,000 were associated with the cell membrane and Mr 52,000 as well as Mr 38,000 were associated with the lysosomes. The 1B10 immunoreactivity was specific to fibroblasts and smooth muscle differentiated fibroblasts within the context of vascular smooth muscle cells.

Actins

Calponin. Developmental isoforms and a low molecular weight variant.

Two-dimensional gel analysis of basic proteins in developing human smooth muscle identifies calponin as a prominent marker of the differentiated phenotype. Adult tissue (human and mouse) typically expresses up to four calponin isoforms, three of which appear sequentially during fetal development: adult myometrial cells express the same three isoforms in primary culture in vitro and these are down-regulated, in reverse order, during the subsequent modulation of phenotype. Monospecific, polyclonal antibodies against calponin identify a lower molecular weight variant of calponin (L-calponin) that is strongly and specifically expressed in adult smooth muscles of the human urogenital tract. L-calponin is down-regulated in benign smooth muscle derived tumors (leiomyoma) and is not expressed in primary cultures of normal uterine tissue.

Animals

Identification of nuclear factor IV/Ku autoantigen in a human 2D-gel protein database. Modification of the large subunit depends on cellular proliferation.

Nuclear Factor IV (NFIV) is a heterodimeric DNA-binding protein from HeLa cells, recognizing molecular ends and is identical to the autoantigenic target Ku. We have identified the two NFIV/Ku subunits, by comigration, in the 2D-gel database of transformed human amnion cell (AMA) proteins. We observed that the large subunit of NFIV/Ku consists of at least 3 charge variants that correspond to SSP IEFs 5705 (81.2 kDa, pI 5.74), 6707 (81.2 kDa, pI 5.67) and 6706 (81.9 kDa, pI 5.60) in the AMA catalogue. The relative amounts of the 2 major variants (IEFs 5705 and 6707) was dependent on the state of cell proliferation. Inhibition of DNA-synthesis by hydroxyurea also changed the relative levels of the variants, whereas aphidicolin or a thymidine block had no effect. These results suggest a possible role for NFIV/Ku in DNA replication.

Amnion

Neuronal protein gene product 9.5 (IEF SSP 6104) is expressed in cultured human MRC-5 fibroblasts of normal origin and is strongly down-regulated in their SV40 transformed counterparts.

Neuronal protein gene product 9.5 (PGP 9.5) most likely identical to ubiquitin carboxyl-terminal hydrolase isozyme L1 (UCH-L1) has been reported to be expressed almost exclusively in neuronal and neuroendocrine tissues. By two-dimensional (2D) immunoblotting, comigration and microsequencing of proteins recovered from 2D gels we have identified PGP 9.5 UCH-L1 as polypeptide IEF SSP 6104 (Mr = 27,000, pI = 5.49) in the comprehensive 2D gel cellular protein database of human embryonal lung MRC-5 fibroblasts [(1989) Electrophoresis 10, 76 115; (1990) Electrophoresis 11, 1072 1113]. This protein is expressed at high levels in quiescent and proliferating cultured normal fibroblasts and is strongly down-regulated (about 10 times) in their transformed counterparts.

Amino Acid Sequence

The master two-dimensional gel database of human AMA cell proteins: towards linking protein and genome sequence and mapping information (update 1991).

The master two-dimensional gel database of human AMA cells currently lists 3801 cellular and secreted proteins, of which 371 cellular polypeptides (306 IEF; 65 NEPHGE) were added to the master images during the last 10 months. These include: (i) very basic and acidic proteins that do not focus under normal running conditions and (ii) low-abundant proteins that can only be detected after prolonged gel exposure. Annotation categories updated in this version include "protein name", "antibody against protein", "cellular localization", and "microsequenced proteins". New entries include "human autoantigens" and "cDNAs". For convenience we have included an alphabetical list of all known proteins recorded in this database. In the long run, the main goal of this database is to link protein and DNA sequencing and mapping information (Human Genome Program) and to provide an integrated picture of the expression levels and properties of the thousands of proteins that orchestrate various cellular functions both under physiological and abnormal conditions.

Cell Line, Transformed

A comprehensive two-dimensional gel protein database of noncultured unfractionated normal human epidermal keratinocytes: towards an integrated approach to the study of cell proliferation, differentiation and skin diseases.

A two-dimensional (2-D) gel database of cellular proteins from noncultured, unfractionated normal human epidermal keratinocytes has been established. A total of 2651 [35S]methionine-labeled cellular proteins (1868 isoelectric focusing, 783 nonequilibrium pH gradient electrophoresis) were resolved and recorded using computer-aided 2-D gel electrophoresis. The protein numbers in this database differ from those reported in an earlier version due to changes in the scanning hardware (Celis et al., Electrophoresis 1990, 11, 242-254). Annotation categories reported include: "protein name" (listing 207 known proteins in alphabetical order), "basal cell markers", "differentiation markers", "proteins highly up-regulated in psoriatic skin", "microsequenced proteins" and "human autoantigens". For reference, we have also included 2-D gel (isoelectric focusing) patterns of cultured normal and psoriatic keratinocytes, melanocytes, fibroblasts, dermal microvascular endothelial cells, peripheral blood mononuclear cells and sweat duct cells. The keratinocyte 2-D gel protein database will be updated yearly in the November issue of Electrophoresis.

Biopsy

Microsequencing of proteins recorded in human two-dimensional gel protein databases.

Sixty-six human proteins recorded in the master transformed human epithelial amnion cells (AMA) (55) and keratinocyte (11) two-dimensional gel protein databases have been microsequenced since the last publication of the AMA database (Electrophoresis 1990, 12, 989-1071). Coomassie Brilliant Blue stained protein spots cut from several (up to 40) dry gels were concentrated by elution-concentration gel electrophoresis, electroblotted onto polyvinylidene difluoride membranes and in situ digested with trypsin. The eluting peptides were separated by reversed-phase high performance liquid chromatography (HPLC), collected individually and sequenced. Computer searches using the FASTA and TFASTA programs from the Genetics Computer Group indicated that 29 of the analyzed polypeptides correspond to hitherto unknown proteins.

Amino Acid Sequence

NCAM in developing mouse gonads and ducts.

The expression of the Neural Cell Adhesion Molecule, NCAM, in mouse gonads and ducts was studied from fetal life to maturity. The methods used were immunocytochemical staining and Western blotting. The immunocytochemical studies showed that the only structures that remain NCAM-positive throughout life were the mesonephric-derived rete ovarii and rete testis. Also in the fetal gonads some somatic cell lining the groups of differentiating germ cells were stained. In the immature as well as in the mature ovary the granulosa cells and oocytes of growing and large follicles--but not of small follicles--were stained. A particularly strong staining of the cytoplasm of the oocyte, healthy as well as atretic, was seen. All cells of the testis remained negative except for weakly stained residual bodies and late spermatids. At all ages the male ducts showed only weak staining, whereas in the female Müllerian duct the epithelium became strongly positive at puberty. The stroma of the Müllerian duct was positive during a transitory period around day 16 of fetal life in both sexes. One-dimensional gel immunoblotting of total protein from gonads, rete and ducts from immature and mature mice showed that only the two largest isoforms of NCAM (NCAM-A and NCAM-B) were present. The gonads and the rete of both sexes and the adult uterus expressed only NCAM-B, whereas NCAM-A was also detected in the adult epididymis. The present findings suggest that NCAM may be involved in the normal development and formation of both the gonads and ducts.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals

Identification of two molecular chaperons (HSX70, HSC70) in mature human erythrocytes.

Two-dimensional gel electrophoresis of cytosolic proteins from mature human erythrocytes combined with immunoblotting revealed the presence of a group of heat shock proteins (HSPs) that included two molecular chaperons of the HSP70 family (HSX70, inducible; HSC70, constitutively expressed) and HSP90. As expected for cells devoid of organelles, erythrocytes do not contain stress proteins that are localized either in the mitochondria (HSP60, glucose-regulated protein (GRP 75) or in the endoplasmic reticulum (GRP78 or Ig heavy chain-binding protein, endoplasmin). Since red cells are unable to replace proteins whose structure has been damaged by environmental changes the results are taken to imply a role for chaperons in monitoring, protecting, and maintaining the structure and stability of erythrocyte proteins.

Electrophoresis, Gel, Two-Dimensional

Human cellular protein patterns and their link to genome DNA sequence data: usefulness of two-dimensional gel electrophoresis and microsequencing.

Analysis of cellular protein patterns by computer-aided 2-dimensional gel electrophoresis together with recent advances in protein sequence analysis have made possible the establishment of comprehensive 2-dimensional gel protein databases that may link protein and DNA information and that offer a global approach to the study of the cell. Using the integrated approach offered by 2-dimensional gel protein databases it is now possible to reveal phenotype specific protein (or proteins), to microsequence them, to search for homology with previously identified proteins, to clone the cDNAs, to assign partial protein sequence to genes for which the full DNA sequence and the chromosome location is known, and to study the regulatory properties and function of groups of proteins that are coordinately expressed in a given biological process. Human 2-dimensional gel protein databases are becoming increasingly important in view of the concerted effort to map and sequence the entire genome.

Amino Acid Sequence

Identification of a group of proteins that are strongly up-regulated in total epidermal keratinocytes from psoriatic skin.

Analysis using two-dimensional (2D) gel electrophoresis of the [35S]-methionine-labelled proteins synthesized by non-cultured total epidermal keratinocytes obtained from normal and psoriatic skin revealed 6 proteins that are strongly up-regulated (5 times or more) in psoriatic skin. These proteins are synthesized at albeit lower levels by keratinocytes from normal and normal-appearing (uninvolved) skin of psoriatic patients, and correspond to isoelectric focusing sample spot numbers 4311 (40.3 kDa), 4003 (12.4 kDa), 5008 (11.9 kDa), 3012 (11.6 kDa), 6016 (11.6 kDa) and 1015 (10.1 kDa) in the normal keratinocyte 2D gel protein database [Celis et al, (1990) Electrophoresis, in press]. These proteins are also detected in the labelling medium indicating that they are at least in part secreted. Given their striking regulatory behavior, these proteins may play a role in the pathogenesis of psoriasis.

Electrophoresis, Gel, Two-Dimensional