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1.
Independent genes coding for three acidic proteins of the large ribosomal subunit from Saccharomyces cerevisiae 总被引:11,自引:0,他引:11
M Remacha M T Sáenz-Robles M D Vilella J P Ballesta 《The Journal of biological chemistry》1988,263(19):9094-9101
The yeast ribosome contains three acidic proteins, L44, L44', and L45, closely related from a structural point of view, that seem to play a functional role similar to that of proteins L7 and L12 in the bacterial ribosome. By screening a cDNA bank in lambda gt11 with specific polyclonal and monoclonal antibodies, recombinant phages expressing each one of the acidic proteins have been cloned. A unique copy of each gene is detected using the phage cDNA inserts as probes in nitrocellulose blots of yeast DNA digested with different restriction enzymes. The inserts were subcloned in the plasmid pUC19, and their physical maps and nucleotide sequences were determined. By using the cDNA inserts as probes in genomic DNA banks, DNA fragments carrying the acidic protein genes have been cloned, characterized, and sequenced. The results conclusively show that the three yeast acidic proteins are coded by independent genes and are not the result of a post-translational modification of the product of a unique gene, as in bacteria. Like most ribosomal protein genes, the gene for protein L44' has an intron and two upstream stimulatory boxes (UASrpg) fitting closely to the consensus sequence. The genes coding for proteins L44 and L45 lack introns and seem also exceptional in other characteristics of their sequences. Proteins L44 and L45 have amino acid sequences with about 80% similarity. Protein L44' is only 63% similar to the other two polypeptides. The three proteins have highly conserved carboxyl termini comprising the last 30 amino acids, and the first 10 amino acids of L44 and L45 are identical. The results cast doubts about the possibility of a similar role for the different acidic ribosomal proteins. 相似文献
2.
3.
R Molina X Filella P Mengual M Prats G Zanon M Daniels A M Ballesta 《The International journal of biological markers》1990,5(1):14-21
MCA serum levels were determined in 27 healthy subjects, 136 with benign pathology (42 breast) and in 289 patients with cancer (247 active). The last group includes 223 patients with breast cancer (96 without metastases, 89 with metastases and 38 no-evidence of disease). CEA and CA15-3 serum levels were determined in all the patients with breast diseases. The mean levels of MCA were 4.7 + 2.4 U/ml in the control group, considering less than 11 U/ml as normal. MCA values were abnormal in 15.4% of patients with benign pathology, mainly in those with liver cirrhosis (8/20) and lung diseases (4/20). In the majority of these cases, the rise was only moderate, lower than 15 U/ml in 97.5% of patients. In malignant diseases, important increments were found in breast cancer (19.8% Mo, 77.5% M1) and ovarian cancer stages III-IV (44.4%). When we compared MCA serum levels with CA15-3 and CEA in breast pathology, a similar specificity was observed: 92.3%, 92.3% and 100% in cases with benign pathology and 92.1%, 94.7%, and 97.4% in NED patients, respectively. MCA and CA15-3 sensitivity was similar in breast cancer without metastases (19.8%) and lower for CEA (16.7%). In patients with breast cancer without metastases, we found a relation between positivity of these tumor markers and prognostic factors (tumor size, nodal involvement). The disease free interval in patients with locoregional breast cancer was shorter in cases with abnormal presurgical levels of some of the tumor markers, but only the difference from MCA was significant (p less than 0.02).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
4.
The renal corpuscle of hibernating and non-hibernating Testudo graeca was studied by means of light and electron microscopy. Renal corpuscles are small and have a glomerular architecture similar to that found in other vertebrates with a limited glomerular filtration rate. In hibernating animals, unlike non-hibernating, some morphological changes took place. The cells of the renal corpuscle were densely packed, podocytes and parietal cells showed a marked cytoplasmic vacuolization, there was a highly developed capillary basement membrane and the endothelial and mesangial cells showed abundant dense granules. These morphological features apparently correspond to a vacuolar degeneration. They may also be the morphological basis of the decrease in the glomerular filtration rate observed during this period. 相似文献
5.
A. De Izuzquiza C. Ascaso E. Fernandez F. Ballesta 《International Journal of Anthropology》1986,1(1):19-23
Finger-prints of the parents of thirty four Down children were compared with thirty four couples with two or more normal children
without a family history of genetic problems.
The parents with children affected by translocation Down Syndrome and those with mosaicism were excluded. A comparison of
the figure distributions in each of the fingers of the two groups shows a different distribution.
Parents of children affected by Down Syndrome occupy an intermediate position between the parents of normal children and the
subjects affected by Down Syndrome.
The total sum of values of A (arch), Lu (ulnar loop), Lt (radial loop) and W in each of the groups were also compared using
a contingency table. A significant difference (p<0,05) was found between both groups. The differences are imputed to the variables
A and L. 相似文献
6.
J. A. Reig S. Viniegra J. J. Ballesta M. Palmero L. M. Gutierrez 《Neurochemical research》1993,18(3):317-323
The role of protein phosphorylation in catecholamine secretion from bovine adrenomedullary chromaffin cells was studied using different protein kinase inhibitors. Naphthalenesulfonamide derivatives as ML9 and ML7, more specific for the myosin light chain kinase, and the calmodulin antagonist W7 inhibited catecholamine secretion 20 and 40% respectively in digitonin-permeabilized chromaffin cells. ML9 also decreased calcium evoked protein phosphorylation of different proteins including tyrosine hydroxylase in permeabilized cells. These naphthalenesulfonamide derivatives showed also an effect in intact cells, ML9 and W7 produced 50% inhibition in catecholamine secretion and45Ca2+ uptake, however H8 had no effect. The partial [3H]nitrendipine binding displacement of these drugs to adrenomedullary membranes suggests that these sulfonamide derivatives could interact directly with L-type calcium channels in intact cells. The results obtained in permeabilized cells suggest a possible role of protein phosphorylation in the regulation of catecholamine secretion in chromaffin cells.The abbreviations used are ML9
1-(5-Chloronaphthalene-1-sulfonyl)1H-hexahydro-1,4-diazepine hydrochloride
- ML7
1-(5-Iodonaphthalene-1-sulfonyl)-1H-hexahydro-1,4 diazepine hydrochloride
- H7
1-(5-isoquinolinesulfonyl)-2-methylpiperazine dihydrochloride
- H8
N-[2-(methylamino)ethyl]-5-isoquinolinesulfonamide dihydrochloride
- W7
N-(6-aminohexyl)-5-chloro-1-naphthalenesulfonamide hydrochloride
- PKI
protein kinase A inhibitor
- HEPES
N-(2-hydroxyethylpiperazine-N-(2 ethanesulfonic acid)
- PIPES
piperazine-N, N-bis (2-ethanesulfonic acid)
- EGTA
[ethylene-bis (oxyethylenenitrilo)] tetraacetic acid
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide gel electrophoresis
- DMEM
Dulbecco's Modified Eagle's medium
- MLC
myosin light chain
- MLCK
myosin light chain kinase
- TH
tyrosine hydroxylase 相似文献
7.
8.
Litman GW; Rast JP; Shamblott MJ; Haire RN; Hulst M; Roess W; Litman RT; Hinds- Frey KR; Zilch A; Amemiya CT 《Molecular biology and evolution》1993,10(1):60-72
Immunoglobulins are encoded by a large multigene system that undergoes
somatic rearrangement and additional genetic change during the development
of immunoglobulin-producing cells. Inducible antibody and antibody-like
responses are found in all vertebrates. However, immunoglobulin possessing
disulfide-bonded heavy and light chains and domain-type organization has
been described only in representatives of the jawed vertebrates. High
degrees of nucleotide and predicted amino acid sequence identity are
evident when the segmental elements that constitute the immunoglobulin gene
loci in phylogenetically divergent vertebrates are compared. However, the
organization of gene loci and the manner in which the independent elements
recombine (and diversify) vary markedly among different taxa. One striking
pattern of gene organization is the "cluster type" that appears to be
restricted to the chondrichthyes (cartilaginous fishes) and limits
segmental rearrangement to closely linked elements. This type of gene
organization is associated with both heavy- and light-chain gene loci. In
some cases, the clusters are "joined" or "partially joined" in the germ
line, in effect predetermining or partially predetermining, respectively,
the encoded specificities (the assumption being that these are expressed)
of the individual loci. By relating the sequences of transcribed gene
products to their respective germ-line genes, it is evident that, in some
cases, joined-type genes are expressed. This raises a question about the
existence and/or nature of allelic exclusion in these species. The
extensive variation in gene organization found throughout the vertebrate
species may relate directly to the role of intersegmental
(V<==>D<==>J) distances in the commitment of the individual
antibody-producing cell to a particular genetic specificity. Thus, the
evolution of this locus, perhaps more so than that of others, may reflect
the interrelationships between genetic organization and function.
相似文献
9.
10.
J. A. Martinez-Menarguez J. Ballesta M. Aviles J. F. Madrid M. T. Castells 《The Histochemical journal》1992,24(4):207-216
Summary The influence of sulphation of mucus glycoproteins in the binding of peanut agglutinin (PNA) to tissue sections has been investigated by means of histochemical techniques at the light- and electron-microscopic level. A sequential methylation-saponification procedure was applied for the desulphation of tissue samples. Labelling by peroxidase- and colloidal gold-conjugated PNA was compared in control and desulphated samples of rat intestinal mucosa. The high-iron-diamine (HID) technique was used as a control for the effectiveness of the desulphation technique, and the Alcian Blue, pH 2.5 (AB 2.5), PAS and phosphotungstic acid-HCl (acid-PTA) techniques served as controls for the integrity of the oligosaccharide chains, respectively. In general, a marked increase of PNA reactivity was observed in desulphated samples when compared with control sections. These findings indicate that sulphation of galactose inhibits the binding of PNA to carbohydrate moieties in tissue sections. Staining patterns obtained with HID, PNA and the desulphation-PNA sequence in the goblet cells of the large intestine suggest a modification of the secretory product stored in these cells as the cell matures and moves from the lower crypt region toward the luminal surface. These modifications were not detected in the small intestine. Ultrastructural detection of PNA-binding sites suggests that galactose residues are incorporated into the oligosaccharide chains of O-liked glycoproteins at the medial cisternae of the Golgi apparatus. However, sulphation occurs at the trans side of the Golgi complex and the trans Golgi network. In conclusion, desulphation procedures are useful for revealing PNA-binding sites. 相似文献