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111.
Detection of Short Protein Coding Regions within the Cyanobacterium Genome: Application of the Hidden Markov Model 总被引:3,自引:0,他引:3
The gene-finding programs developed so far have not paid muchattention to the detection of short protein coding regions (CDSs).However, the detection of short CDSs is important for the studyof photosynthesis. We utilized GeneHacker, a gene-finding programbased on the hidden Markov model (HMM), to detect short CDSs(from 90 to 300 bases) in a 1.0 mega contiguous sequence ofcyanobacterium Synechocystis sp. strain PCC6803 which carriesa complete set of genes for oxygenic photosynthesis. GeneHackerdiffers from other gene-finding programs based on the HMM inthat it utilizes di-codon statistics as well. GeneHacker successfullydetected seven out of the eight short CDSs annotated in thissequence and was clearly superior to GeneMark in this rangeof length. GeneHacker detected 94 potentially new CDSs, 9 ofwhich have counterparts in the genetic databases. Four of thenine CDSs were less than 150 bases and were photosynthesis-relatedgenes. The results show the effectiveness of GeneHacker in detectingvery short CDSs corresponding to genes. 相似文献
112.
113.
H. Akagi A. Nakamura R. Sawada M. Oka T. Fujimura 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(7-8):948-951
Twelve Japanese rice cultivars were converted to CMS by asymmetric protoplast fusion with MTC-5A, the cytoplasm of which was derived from an indica rice, Chinsurah Boro II. With the exception of the cybrids that had a nucleus from Hoshiyutaka, most of these cybrid plants were sterile. The unique sequence downstream from the mitochondrial atp6 of MTC-5A was specifically amplified in the sterile cybrid plants by PCR. All progenies of the cybrid plants carrying this unique sequence were sterile. On the other hand, in some of the sterile cybrid plants in which the unique sequence was not amplified by PCR, fertility was recovered in their progenies. Somaclonal mutation may have caused sterility in these cybrids. Only the cybrid plants that had the unique sequence detected by PCR were CMS. Thus, the CMS plants can be selected rapidly and easily by PCR, at an early stage of plant regeneration. Soon after transplanting the regenerated plants to a green house, fertile cybrids and sterile cybrids produced by somaclonal mutation can be removed. These findings also show that the unique region downstream from atp6 is tightly linked with the CMS phenotype. 相似文献
114.
115.
Tomomi Hidaka Masao Goda Tomohisa Kuzuyama Naomi Takei Makoto Hidaka Haruo Seto 《Molecular & general genetics : MGG》1995,249(3):274-280
The biosynthetic pathway for production of the antibiotic fosfomycin by Streptomyces wedmorensis consists of four steps including the formation of a C-P bond and an epoxide. Fosfomycin production genes were cloned from genomic DNA using S. wedmorensis mutants blocked at different steps of the biosynthetic pathway. Four genes corresponding to each of the biosynthetic steps were found to be clustered in a DNA fragment of about 5 kb. Nucleotide sequencing of a large fragment revealed the presence of ten open reading frames, including the four biosynthetic genes and six genes with unknown functions. 相似文献
116.
Isolation and Characterization of Hardening-Induced Proteins in Chlorella vulgaris C-27: Identification of Late Embryogenesis Abundant Proteins 总被引:4,自引:0,他引:4
Honjoh Ken-ichi; Yoshimoto Makoto; Joh Toshio; Kajiwara Taishin; Miyamoto Takahisa; Hatano Shoji 《Plant & cell physiology》1995,36(8):1421-1430
Hardening-induced soluble proteins of Chlorella vulgaris BeijerinkIAM C-27 (formerly Chlorella ellipsoidea Gerneck IAM C-27) wereisolated and purified by two-dimensional high-performance liquidchromatography (2D-HPLC) on an anion-exchange column, with subsequentreversed-phase chromatography. Some of the proteins were resolvedby SDS-PAGE, characterized by amino-terminal sequencing andidentified by searching for homologies in databases. Separationof the soluble proteins during the hardening of Chlorella bya combination of 2D-HPLC and SDS-PAGE revealed that at least31 proteins were induced or increased in abundance. Of particularinterest was the induction after 12 h of a 10-kDa protein withthe amino-terminal amino acid sequence AGNKPITEQISDAVGAAGQKVGand the induction after 6 h of a 14-kDa protein with the amino-terminalsequence ALGEESLGDKAKNAFEDAKDAVKDAAGNVKEAV. The amino-terminalsequences of these proteins indicated that they were homologousto late embryogenesis abundant (LEA) proteins. Furthermore,the level of a 22-kDa protein also increased after 12 h. Theamino-terminal sequence of this protein, AAPLVGGPAPDFTAAAVFD,indicated that it was homologous to thioredoxin peroxidase. (Received June 9, 1995; Accepted September 12, 1995) 相似文献
117.
Alejandro Vazquez-Tello Makoto Hidaka Takeshi Uozumi 《Plant Cell, Tissue and Organ Culture》1995,40(2):169-177
Embryogenic cell suspensions of Lavatera thuringiaca L. were established from leaf petiole and shoot regeneration was achieved when cells were plated on medium without growth regulators. We tested three methods for protoplast culture, isolated from a one-year old embryogenic cell suspension, to determine the best conditions for L. thuringiaca protoplast culture and shoot regeneration. The highest protoplast plating efficiency was obtained with the agaroseembedded method, reaching 30%, while the nursing culture method gave 5% when the protoplasts were plated over Whatman paper No. 2. However, the same nursing culture failed to produce protoplast-derived microcalluses when the protoplasts were plated on a nitrocellulose filter. The liquid thin layer method gave the lowest plating efficiency with only 0.5%. Shoot regeneration from protoplast-derived microcalluses was achieved in two steps; first, globular embryo development was favored in medium low in auxin (2,4-d and BA at 0.01 and 0.05 mg 1-1, respectively), second, the globular embryos further differentiate into shoots in medium without growth regulators or in medium containing GA3 (0.5 to 1.0 mg 1-1).Abbreviations 2,4-d
2,4-dichlorophenoxyacetic acid
- BA
benzyladenine
- GA3
gibberellic acid
- NAA
-naphthaleneacetic acid
- IBA
indole-3-butyric acid 相似文献
118.
Makoto Handa Akira Suzuki Sadayuki Shoji Kuninobu Kasuga Kunihisa Sogabe 《Inorganica chimica acta》1995,230(1-2):41-44
A vanadyl complex with perfluorinate phthalocyanine, VOPcF16, was prepared. The monomer-dimer solvent dependence was confirmed based on the solvent effect for the Q-band position-that is, VOPcF16 exists as a monomer in a nonpolar solvent such as benzene, but dimerizes in a polar solvent such as acetone. Electron spin resonance data also supported the solvent dependence found. In addition, the substituent effect of fluorine atoms on the redox properties was investigated by measuring the cyclic voltammograms in dichloromethane. On the reduction side, three redox couples were observed, the first two of which were assigned as being due to the reduction of the phthalocyanine ring (to LUMO), whose potentials are 0.4–0.5 V higher than those of the tetra-t-butyl and octabutoxy derivatives, VOPc(t-Bu)4 and VOPc(O-n-Bu)8. 相似文献
119.
The inner layer of vitelline membrane is an investment of avian ovum at the time of ovulation, but its formation is poorly understood. In order to elucidate the origin of the inner layer of vitelline membrane, a 33 kDa protein, one of the components of the inner layer, was purified from quail eggs and polyclonal antibody was raised against this protein. The tissue distribution of protein interacted with the antibody was studied by Western blotting technique. No immunoreactive component could be observed in extracts of liver, kidney, heart, lung, small intestine, brain, infundibulum, albumen-secreting region of oviduct, uterus, and wall of small white follicles. The intensive band was detected in the granulosa layer, which was isolated from the large preovulatory follicles as a monolayer of granulosa cells sandwiched between the inner layer of vitelline membrane and the basal lamina. The granulosa cells isolated from the granulosa layer also reacted with this antibody. Theca layer had no immunoreactive components. The position of the band of the 33 kDa protein on SDS-PAGE was sifted to higher molecular weight in follicular tissues as compared with that in the laid eggs, indicating that the structural change of the protein occurs after ovulation. These studies indicate that the material reactive to the antibody raised against a 33 kDa protein of quail vitelline membrane is synthesized by the granulosa cells. 相似文献
120.
Aruto Yoshida Tomoka Hara Hiroshi Ikenaga Makoto Takeuchi 《Glycoconjugate journal》1995,12(6):824-828
By employing a bovine UDP-N-acetylgalactosamine: polypeptideN-acetylgalactosaminyl transferase (O-GalNAc transferase) cDNA as a probe, we isolated four overlapping cDNAs from a porcine lung cDNA library. Both the nucleotide sequence of the porcine cDNA and the predicted primary structure of the protein (559 amino acids) proved to be very similar to those of the bovine enzyme (95% and 99% identity, respectively). Transient expression of the clone in COS-7 cells, followed by enzymatic activity assays, demonstrated that this cDNA sequence encodes a porcine O-GalNAc transferase. The intracellular O-GalNAc transferase activity was increased approximately 100-fold by transfecting cells with the porcine cDNA.Abbreviations O-GalNAc transferase
UDP-N-acetylgalactosamine: polypeptideN-acetylgalactosaminyltransferase
- PCR
polymerase chain reaction
- SDS
sodium dodecyl sulfate
- PAGE
polyacrylamide gel electrophoresis
- GnT-III
UDP-N-acetylglucosamine: -mannoside -1,4N-acetylglucosaminyltransferase III 相似文献