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91.
92.
The genomic sequences of several RNA plant viruses including cucumber mosaic virus, brome mosaic virus, alfalfa mosaic virus
and tobacco mosaic virus have become available recently. The former two viruses are icosahedral while the latter two are bullet
and rod shaped, respectively in particle morphology. The non-structural 3a proteins of cucumber mosaic virus and brome mosaic
virus have an amino acid sequence homology of 35% and hence are evolutionarily related. In contrast, the coat proteins exhibit
little homology, although the circular dichroism spectrum of these viruses are similar. The non-coding regions of the genome
also exhibit variable but extensive homology. Comparison of the brome mosaic virus and alfalfa mosaic virus sequences reveals
that they are probably related although with a much larger evolutionary distance. The polypeptide folds of the coat protein
of three biologically distinct isometric plant viruses, tomato Bushy stunt virus, southern bean mosaic virus and satellite
tobacco necrosis virus have been shown to display a striking resemblance. All of them consist of a topologically similar 8-standard
β-Barrel. The implications of these studies to the understanding of the evolution of plant viruses will be discussed. 相似文献
93.
S Millar D C Hayward C A Read M J Browne R V Santelli F Garcia Vallejo M T Pueyo A Zaha D M Glover F J Lara 《Gene》1985,34(1):81-86
We have constructed a library of recombinant phage containing DNA from salivary gland chromosomes of Rhynchosciara americana. We have isolated phage from this library that carry sequences homologous to cDNA clones that hybridize in situ to the DNA puffs at the polytene chromosome regions C3 and C8. This has enabled us to demonstrate a 16-fold amplification of the genomic DNA sequences at these regions during DNA-puffing. At the C8 site there is a sequence element that has characteristics of 'scrambled' moderately repetitive DNA. This is located within 3 kb from the gene encoding a 1.95-kb mRNA. We have assayed restriction fragments from the two DNA puffs for Ars activity in yeast. The only strong Ars activity is associated with a part of the moderately repetitive DNA element from the C8 puff which is not present at this site in all animals. 相似文献
94.
Nonrandom insertion of Tn5 into cloned human adenovirus DNA 总被引:4,自引:0,他引:4
95.
96.
97.
Sequence of Guinea Pig Myelin Basic Protein 总被引:5,自引:5,他引:0
Gladys E. Deibler Russell E. Martenson Henry C. Krutzsch† Marian W. Kies 《Journal of neurochemistry》1984,43(1):100-105
This paper proposes a tentative amino acid sequence of guinea pig myelin basic protein obtained by comparison of peptide fragments of the guinea pig and bovine proteins. Analyses of the tryptic peptides confirmed the known sequence differences in the NH2-terminal half of the molecule and showed that in the COOH-terminal half of the guinea pig protein Ser131 was missing, Ala136 - His137 was deleted, Leu140 was replaced by Phe, and an extra Ala was inserted somewhere within sequence 142-151 (tryptic peptide T23 ). Sequence determination of guinea pig tryptic peptides corresponding to residues 130-134 ( T20 ), 135-138 ( T21 ), and 142-151 ( T23 ) of the bovine protein confirmed the above sequence changes and placed the extra Ala between Gly142 and His143 . The sequence of the region corresponding to bovine residues 130-143 is thus Ala-Asp-Tyr-Lys-Ser-Lys-Gly-Phe-Lys-Gly-Ala-His. No species differences were observed in the amino acid compositions of the remaining tryptic peptides obtained from the COOH-terminal half of the molecule. Based upon these results, the guinea pig basic protein contains 167 amino acid residues and has a molecular weight of 18,256. 相似文献
98.
Many studies have established a correlation of differences in the activities of various muscle types with differences in the expression of myosin isoforms. In this paper we report the sequence determination of myosin light chain-2 from rabbit slow skeletal (LC2s) and ventricular (LC2v) nmscles. We sequenced tryptic peptides from LC2v which account for all except a few terminal amino acid residues. The major part (87 residues) of the rabbit LC2s sequence, obtained from tryptic and cyanogen bromide (CNBr) peptides, was found to be identical to rabbit LC2v. Our results provide the first sequence information on LC2s from any species, and lend strong support to the hypothesis that LC2s and LC2v are identical. Comparisons of rabbit LC2v and LC2s with rabbit LC2f (from fast skeletal muscle), and also with chicken LC2f and LC2v, show clearly that LC2s and LC2v from mammalian and avian species are more closely related to each other than they are to LC2f isoforms from the same species. 相似文献
99.
The amino acid sequences of cytochrome c553 from the eukaryotic red alga Porphyridium cruentum and from the prokaryotic cyanobacterium Aphanizomenon flos-aquae have been determined from the tryptic and cyanogen bromide peptides. The results indicate that a charged region of these proteins has evolved with special rapidity to accomodate a rapid evolution of a binding site in the P700 electron acceptor complex. 相似文献
100.
Summary An EcoRI 2.7 kbp fragment from Chlorella ellipsoidea chloroplast DNA (cpDNA) cloned in YIp5 was shown to promote autonomous replication in Saccharomyces cerevisiae. The fragment was localized in the small single copy region close to the inverted repeat. The ARS activity (autonomously replicating sequences in yeast) was found to be confined within a subclone of a ca. 300 bp HindIII fragment. Sequence analysis of this fragment revealed its high AT content and the presence of several direct and inverted repeats and a few elements that were related to the yeast ARS consensus sequence. Electron microscopic studies revealed that this sequence did not coincide with the primary replication origin of chloroplast DNA. The functioning of this sequence as a possible origin of plasmid replication in vivo is discussed. This is the first report on Chlorella cpDNA sequence. re]19850821 rv]19851211 ac]19851216 相似文献