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The mouse mammary tumor virus can induce mammary tumors in mice by proviral activation of an evolutionarily conserved cellular oncogene called int-1. Here we present the nucleotide sequence of the human homologue of int-1, and compare it with the mouse gene. Like the mouse gene, the human homologue contains a reading frame of 370 amino acids, with only four substitutions. The amino acid changes are all in the hydrophobic leader domain of the int-1 encoded protein, and do not significantly alter its hydropathic index. The conservation between the mouse and the human int-1 genes is not restricted to exons; extensive parts of the introns are also homologous. Thus, int-1 ranks among the most conserved genes known, a property shared with other oncogenes.
The mitochondrial NADH-ubiquinone reductase (complex I) is an assembly of approximately 26 different polypeptides. In vertebrates and invertebrates, seven of its subunits are the products of genes in the mitochondrial DNA, and homologues of these genes have been found previously in the chloroplast genomes of Marchantia polymorpha and Nicotiana tabacum, although their function in the chloroplast is unknown. The remainder of the subunits of the mitochondrial complex are nuclear gene products that are imported into the organelle, amongst them the 49 kd subunit, a component of the iron--sulphur subcomplex of the enzyme. In the present work, the N-terminal sequence of this protein has been determined, and this has been used to design two mixtures of synthetic oligonucleotides, each containing 32 different sequences 17 bases long. These mixtures have been used as hybridization probes to isolate cDNA clones from a bovine library. The DNA sequences of these clones have been determined and they encode the mature 49 kd protein, with the exception of amino acids 1 and 2. The protein sequence of 430 amino acids is closely related to those of proteins that are encoded in open reading frames (ORFs) present in the chloroplast genomes of M.polymorpha and N.tabacum. Only one cysteine is conserved and the sequences provide no indication that the 49 kd protein contains iron--sulphur centres. These ORFs are found in the single copy regions of chloroplast DNA in close proximity to four of the homologues of the mammalian mitochondrial genes that encode subunits of complex I.(ABSTRACT TRUNCATED AT 250 WORDS)
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Preventive detention is imposed by court order if a dangerous criminal shows a disposition to relapse. The negative criminal prognosis should be given by a psychiatric expert based on considerations about the criminal's personality traits. Matters of preventive detention are important for forensic psychiatry, but so far have rarely been discussed. This article presents related problems and offers-under special consideration of problematic personality traits or personality disorders-practical guidelines for expert testimony. Our considerations should serve as a thought-provoking stimulus for further psychiatric discussions about this topic.
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We have identified a possible mutation which characterizes A2 alleles (a minor subtype of A) at the human histo-blood group ABO locus based on polymerase chain reaction (PCR) of genomic DNA, followed by nucleotide sequencing of the amplified fragments. The A2 subtype has a single base deletion near the carboxyl terminal. As a result of frame-shifting, A2 transferase possesses an extra domain. Introduction of this single base deletion into the A1 transferase cDNA expression construct drastically decreased the A transferase activity in DNA-transfected HeLa cells.
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More than one-third of the turnip yellow mosaic virus (TYMV) genome simultaneously encodes two ORFs. We have investigated the functions of the overlapping coat protein ORF and readthrough domain of ORF-206 in the 3' region of the genome. TYMC-206 RNA, in which a second stop codon has been positioned to prevent ORF-206 readthrough, induced infections in protoplasts and plants that were indistinguishable from wild type. ORF-206 readthrough is thus nonessential. Nevertheless, TYMV-221 RNA, in which the ORF-206 stop codon was replaced with a tyrosine codon to force readthrough, was infectious to protoplasts, suggesting that a role for ORF-206 readthrough under certain conditions is possible. TYMV RNA variants that produce truncated or no coat protein were used to show that the coat protein is dispensable for local movement but necessary for systemic spread of virus in plants. Studies in protoplasts showed that (-) RNA levels are normal in the absence of coat protein, but (+) strand levels are decreased about 10-fold relative to wild-type infections. A mutant with a short C-terminal coat protein extension that formed virions less stable than normal demonstrated the protective role of capsids toward genomic RNA. The evolutionary implications of the dense information content of the TYMV genome are discussed.
We present examples of results from our studies of auditory primary afferent nerve fibers and populations of such fibers in the frog and gerbil. We take advantage of the natural dithering effect of internal noise, where it is sufficient, to construct highly predictive descriptive models (based on the Wiener series with kernels derived from white-noise analysis). Where the internal noise is insufficient, we enhance dithering by applying external acoustic noise together with our stimuli. Using acoustic noise as a background sound, orthogonal to the stimulus waveform, we show that under some circumstances such background sound can enhance the ability of individual fibers and populations of fibers to encode the stimulus waveform.
OBJECTIVES: This work aimed to find out whether the human cortical 'tonotopy' represents the true fundamental frequency (Fo) of complex sounds, or the center frequency CF at which harmonics peak in the audio spectrum. Indeed, complex periodic sounds (such as those of the human voice, musical instruments, etc.) comprise a 'fundamental component' (Fo) and its 'harmonics' (2Fo, 3Fo, ...nFo). These often peak around a certain frequency CF. As Fo and CF are confounded in pure (sinusoidal) tones, the question of whether Fo or CF is represented through tonotopy had been hitherto unresolved. METHODS: Whole-head recordings of brain electrical activity were obtained for 16 subjects submitted to an array of 9 different series of sounds (3 Fox3 CF). Electrophysiological data were analyzed separately for each sound and each subject with brain functional imaging and dipole reconstruction. RESULTS: Equivalent dipole sources of N1 components were, significantly for all subjects, more and more frontally oriented as CF increased, independently of Fo. CONCLUSIONS: Sounds are mapped in both the right and the left primary auditory cortices according to the spectral profiles of their harmonics (CF), rather than their fundamental frequencies (Fo).
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