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K Semba

Publications and source records attributed to K Semba.

At least 109 records · Page 6Linked to original sources
PubMed1987

Characterization of cDNA clones for the human c-yes gene.

Three c-yes cDNA clones were obtained from poly(A)+ RNA of human embryo fibroblasts. Sequence analysis of the clones showed that they contained inserts corresponding to nearly full-length human c-yes mRNA, which could encode a polypeptide of 543 amino acids with a relative molecular weight (Mr) of 60,801. The predicted amino acid sequence of the protein has no apparent membrane-spanning region or suspected ligand binding domain and closely resembles pp60c-src. Comparison of the sequences of c-yes and v-yes revealed that the v-yes gene contains most of the c-yes coding sequence except the region encoding its extreme carboxyl terminus. The region missing from the v-yes protein is the part that is highly conserved in cellular gene products of the protein-tyrosine kinase family.

Amino Acid Sequence↗
PubMed1987

Isolation and sequencing of cDNA clones homologous to the v-fgr oncogene from a human B lymphocyte cell line, IM-9.

Two c-fgr cDNA clones were isolated from a cDNA library derived from a human B lymphocyte cell line, IM-9. Sequence analysis of the clones showed that they contained inserts corresponding to nearly full-length human c-fgr mRNA, which could encode a polypeptide of 529 amino acids with a calculated molecular weight of 59,478. Although the amino acid sequence between Gly-78 and the carboxy-terminus of the c-fgr is highly homologous to the corresponding sequence of the c-yes protein, the homology between the two proteins is low in the amino-terminal proximal region. Northern blot hybridization analysis using the c-fgr specific sequence showed that the c-fgr mRNA was expressed at higher level in the liver than in the brain, lung, or kidney of a human fetus.

Amino Acid Sequence↗
PubMed1986

Dorsal horn cells in the cat responding to stimulation of the plantar cushion.

Dorsal horn cells (DHC) in the spinal cord of cats responding to low threshold mechanical stimulation of the plantar cushion (PC), labelled with intracellular horseradish peroxidase, displayed a wide variety of anatomical and physiological characteristics, some of which were quite consistent within a given lamina. These DHC had cell bodies located medially in spinal segment L7, in laminae III, IV and VI. Dendritic fields varied greatly, for the most part conforming to patterns corresponding to their locations in the dorsal horn. Axon collaterals of most DHC ramified near their cell bodies, chiefly projecting ventral ward within the same lamina as the cell body or into more ventral laminae. Cells with the shortest central delays had cell bodies in laminae III and IV. Response latencies of DHC to PC stimulation were only slightly greater than the latencies of primary afferent fibers. Lamina IV cells had mechanical thresholds comparable to those of the primary afferents, significantly lower than the thresholds of cells of laminae III or VI. The receptive fields (RF) of the lamina IV cells were significantly larger than those of the primary afferent fibers or of the lamina VI cells. Relationships among RF area, mediolateral locations of cell bodies and dendritic spread were investigated.

Animals↗
PubMed1986

The facial "motor" nerve of the rat: control of vibrissal movement and examination of motor and sensory components.

Rhythmical whisking of the mystacial vibrissae at about 7 Hz during exploration is one of the most conspicuous behavioral patterns in the rat. To identify the final common pathway for vibrissal movement, individual motor branches of the facial nerve, including the posterior auricular, temporal, zygomatic, buccal, marginal mandibular, cervical, stylohyoid, and posterior digastric branches, were cut, either singly or in various combinations. We found that vibrissal movement could be abolished only by transection involving the buccal branch and the upper division of the marginal mandibular branch. To trace back the central origins of the buccal and marginal mandibular, as well as the other branches of the facial nerve, all distal to the stylomastoid foramen, horseradish peroxidase (HRP) was applied to the cut proximal ends of these individual branches. The retrograde HRP labelling in the facial motor nucleus revealed topographical representation of these branches in which the buccal and marginal mandibular branches were represented laterally. The stylohyoid and posterior digastric branches originated from cells in the suprafacial nucleus. Consistent with earlier observations with intramuscular HRP injections, the motoneuronal population devoted to vibrissal movement did not seem to be substantially larger than that for other facial movements. An additional examination was made of the labelled afferent component of the facial motor nerve. We confirmed and extended previous findings that none of the above facial motor nerve branches, except the posterior auricular branch, contained a significant number of afferent fibers originating from the geniculate ganglion, the sensory ganglion of the seventh nerve. In addition, no labelling was seen in the mesencephalic trigeminal nucleus or trigeminal ganglion. These findings, in combination, suggest that, with the exception of the posterior auricular branch, all the facial motor nerve branches, including those involved in vibrissal movement, are almost entirely efferent.

Animals↗
PubMed1986

In vitro transcription of infectious RNAs from full-length cDNAs of tobacco mosaic virus.

We have cloned full-length double-stranded cDNAs of tobacco mosaic virus (TMV) (tomato strain L) RNA into a transcription vector, pPM1, which facilitates the correct transcription initiation from the first nucleotide of the inserted double-stranded cDNA, corresponding to the 5' end of TMV RNA. When plasmid DNA is linearized at a unique restriction site (Mlu I) introduced just downstream of the double-stranded cDNA insert and used as a template for in vitro transcription by Escherichia coli RNA polymerase in the presence of m(7)GpppG, the transcribed RNAs are infectious for tobacco plants. A simple reconstitution procedure increases the infectivity >100 times. Unexpectedly, both the uncapped transcript and the transcript from the uncut plasmid DNA are also infectious, although their infectivities are very low. The progeny viruses multiplying in tobacco plants accurately reflect the cloned sequence. By the same method, we succeeded in the in vitro transcription of infectious RNA of attenuated strain L(11)A, which is phenotypically distinguishable from wild-type TMV on both tobacco and tomato plants.

Journal Article↗
PubMed1986

yes-related protooncogene, syn, belongs to the protein-tyrosine kinase family.

An src/yes-related novel gene named syn (SYN in human gene nomenclature) has been identified in the human genome on chromosome 6 and characterized by molecular cloning. Nucleotide sequence analysis of cDNA clones showed that the c-syn gene could encode a protein-tyrosine kinase that is very similar in primary structure to the v-yes and human c-src proteins. A 2.8-kilobase transcript of the c-syn gene, which differs in size from those of the c-yes, c-src, and c-fgr genes, was observed in various cell types. These results show that syn is a new member of the tyrosine kinase oncogene family.

Amino Acid Sequence↗
PubMed1986

Structure, expression, and chromosomal location of the human c-fgr gene.

The nucleotide sequence of seven exons of the human c-fgr gene, a cellular homolog of the oncogene of Gardner-Rasheed feline sarcoma virus, was determined. Twenty-six independent genomic clones were obtained from a human gene library with a DNA clone of Y73 avian sarcoma virus oncogene, v-yes, as a probe under relaxed hybridization conditions. Restriction mapping and partial sequence analyses revealed that two of these clones were derived from the c-fgr gene, distinct from the c-yes gene. Interestingly, the splicing points of the c-fgr gene were identical with those of the c-src gene throughout the seven exons, suggesting that the two proto-oncogenes were generated by gene duplication of an ancestral gene containing intervening sequences. On RNA blot hybridization the major transcript was found to be 2.6 kilobase long. Two additional transcripts of 3.5 and 4.7 kilobases were also detected. Furthermore, karyotype analysis of several human-mouse hybrid cells and Southern blot analyses of DNAs of the hybrids with a human c-fgr locus-specific probe showed that this gene is located on chromosome 1.

Animals↗
PubMed1986

Localization of a novel v-erbB-related gene, c-erbB-2, on human chromosome 17 and its amplification in a gastric cancer cell line.

The c-erbB-2 gene is a v-erbB-related proto-oncogene which is distinct from the gene encoding the epidermal growth factor receptor. By using two independent methods, hybridization of both sorted chromosomes and metaphase spreads with cloned c-erbB-2 DNA, we mapped the c-erbB-2 locus on human chromosome 17 at q21, a specific breakpoint observed in a translocation associated with acute promyelocytic leukemia. Furthermore, we observed amplification and elevated expression of the c-erbB-2 gene in the MKN-7 gastric cancer cell line. These data suggest possible involvement of the c-erbB-2 gene in human cancer.

Cell Line↗
PubMed1986

Nakahara memorial lecture. Non-receptor type protein-tyrosine kinases closely related to src and yes compose a multigene family.

We have determined the total coding sequence of human c-yes, a non-receptor type protein-tyrosine kinase gene, and found that the c-yes gene closely resembles the c-src gene. Recently, two new genes, syn and lyn, were found to encode proteins closely related to the yes product. In addition, we also determined the partial sequence of fgr. These genes together with lck reported by two American groups have very closely related structures and are thought to compose a closely related group of non-receptor type protein-tyrosine kinases. Partial analysis of the structures of these genes indicated that they have identical splicing junctions at all sites so far examined. On the other hand, the erbB-1/EGF (epidermal growth factor) receptor gene and the erbB-2/neu gene have completely different splicing junctions from those of the above gene group even in the kinase domain, although these genes also have protein kinase activity specific for tyrosine residues and the erbB-1 and -2 genes share splicing sites. These results suggest that the genes of the group of six non-receptor type kinases and those of the erbB-1 and erbB-2 gene group are descendants evolved by duplication of two distinct ancestor genes and are members of two distinct multi-gene families. The genes coding for protein kinases may be members of a super-family including multiple distinct gene families.

Amino Acid Sequence↗
PubMed1985

4-Aminopyridine induces expansion of cutaneous receptive fields of dorsal horn cells.

Systemic administration of 4-aminopyridine (4-AP) increased the size of the cutaneous receptive fields of 9 of the 15 dorsal horn cells tested. These receptive fields were on the feet and toes of the hind limbs of cats. Receptive field sizes increased with increasing doses of 4-AP. However, 4-AP administration did not change the responses of dorsal horn cells to graded mechanical stimuli administered near the centers of their receptive fields.

4-Aminopyridine↗
PubMed1985

Location of the c-yes gene on the human chromosome and its expression in various tissues.

Analysis of DNA from human embryo fibroblasts showed that ten Eco RI fragments were hybridizable with the Yamaguchi sarcoma virus oncogene (v-yes). Four of the Eco RI fragments were assigned to chromosome 18 and one to chromosome 6. There was evidence for multiple copies of yes-related genes in the human genome; however, only a single RNA species, 4.8 kilobases in length, was related to yes in various cells.

Animals↗
PubMed1985

An electron microscopic study of terminals of rapidly adapting mechanoreceptive afferent fibers in the cat spinal cord.

The intra-axonal horseradish peroxidase technique was used to examine the central terminals of 7 A beta primary afferent fibers from rapidly adapting (RA) mechanoreceptors in the glabrous skin of the cat's hindpaw. At the light microscopic level, labelled collaterals were seen to bear occasional boutonlike swellings, mostly (75-82%) of the en passant type. These swellings were distributed more or less uniformly from lamina III to a dorsal part of lamina VI in the dorsal horn, over a maximum longitudinal extent of about 4 mm. At the electron microscopic level, we observed that labelled boutons of RA afferent fibers were 1.0 to 3.3 micrometers in longest sectional dimension, and contained clear, round synaptic vesicles. They frequently formed asymmetric axospinous and axodendritic synapses and commonly appeared to receive contacts from unlabelled structures containing flattened or pleomorphic vesicles plus occasional large dense-cored vesicles. The examination of synaptic connectivity over the entire surface of individual boutons indicated that RA afferent boutons each made contacts with an average of one spine and one dendrite and, in addition, appeared to be postsynaptic to an average of two unlabelled vesicle-containing structures. This synaptic organization was, in general, more complex than that we had seen previously in Pacinian corpuscle (PC) and slowly adapting (SA) type I mechanoreceptive afferent fibers. Our findings indicate that RA, SA, and PC afferent terminals, while displaying some differential synaptic organizations, have many morphological and synaptological characteristics in common. These afferent terminals, in turn, seem to be generally distinguishable from the terminals of muscle spindle Ia afferents or unmyelinated primary afferents.

Animals↗
PubMed1985

A v-erbB-related protooncogene, c-erbB-2, is distinct from the c-erbB-1/epidermal growth factor-receptor gene and is amplified in a human salivary gland adenocarcinoma.

From a human genomic library, we obtained six v-erbB-related DNA clones. A DNA probe prepared from one of the clones, lambda 107, hybridized to EcoRI fragments of 6.4 and 13 kilobase pairs of human DNA. Neither of these fragments was amplified in A431 vulva carcinoma cells, in which the gene encoding the epidermal growth factor receptor is amplified. In addition, the probe from lambda 107 hybridized with a single, 4.8-kilobase poly(A)+ RNA species and did not react with EGF receptor mRNA. Thus, we conclude that clone lambda 107 represents a v-erbB-related gene (c-erbB-2) that is distinct from the EGF receptor gene. In contrast, the other five clones were shown to represent the EGF receptor gene (c-erbB-1). Partial nucleotide sequence analysis of the lambda 107 insert showed that this clone contained at least seven putative exons and that six of them could encode the kinase domain characteristic of protein products of the src oncogene family. Southern blot analysis showed close similarity of the restriction patterns of the rat c-erbB-2 gene and the rat neu oncogene, suggesting possible involvement of c-erbB-2 in human cancer. In fact, approximately 30-fold amplification of c-erbB-2 was observed in a human adenocarcinoma of the salivary gland.

Adenocarcinoma↗
PubMed1985

Human c-f gr gene does not contain coding sequence for actin-like protein.

f gr is a member of the protein kinase oncogene family and was found to have the highest homology to yes gene among the members of the family. Using a v-yes probe, a molecular clone of human c-f gr locus was isolated from a genomic library. Nucleotide sequence determination revealed that the actin gene-like sequence found in v-f gr gene was absent at the corresponding position of the c-f gr gene. Thus, the v-f gr gene product is considered to be a tri-chimeric gene product consisting of viral gag gene and two distinct cellular genes, actin gene and the proto-f gr gene.

Actins↗
PubMed1985

Regional mapping of the human proto-oncogene c-yes-1 to chromosome 18 at band q21.3.

Human proto-oncogene c-yes-1 homologous to the viral oncogene (v-yes) of an avian Y73 sarcoma virus was mapped to region q21.3 of chromosome 18 by in situ hybridization. This finding confirmed and more rigidly substantiated the previous assignment which was based on analyses of human X mouse somatic cell hybrids and Southern blots.

Chromosome Mapping↗