[The quality of life in relatives giving care to patients with psychotic disorders is mainly determined by their internal locus of control].

Introduction: The presented study examines to which extent the quality of life and experiences of relatives giving care to patients with psychotic disorders are being influenced by patient- or relative-dependent factors.

Material And Methods: The quality of life and experiences of care-giving of 33 relatives of patients with a schizophrenic spectrum disorder were assessed. Applying a multiple regression model, they were correlated to the relatives' internal locus of control as well as to data referring to the patients' disease.

In-frame overlapping genes: the challenges for regulating gene expression.

In-frame overlapping genes in phage, plasmid and bacterial genomes permit synthesis of more than one form of protein from the same gene. Having one gene entirely within another rather than two separate genes presumably precludes recombination events between the identical sequences. However, studies of such gene pairs indicate that the overlapping arrangement can make regulation of the genes more difficult.

Translation at higher than an optimal level interferes with coupling at an intercistronic junction.

In pairs of adjacent genes co-transcribed on bacterial polycistronic mRNAs, translation of the first coding region frequently functions as a positive factor to couple translation to the distal coding region. Coupling efficiencies vary over a wide range, but synthesis of both gene products at similar levels is common. We report the results of characterizing an unusual gene pair, in which only about 1% of the translational activity from the upstream gene is transmitted to the distal gene.

Emerging features of mRNA decay in bacteria.

The problem of mRNA decay in E. coli has recently seen exciting progress, with the discoveries that key degradation enzymes are associated together in a high molecular weight degradosome and that polyadenylation promotes decay. Recent advances make it clear that mRNA decay in bacteria is far more interesting enzymatically than might have been predicted.

Roles of polyadenylation and nucleolytic cleavage in the filamentous phage mRNA processing and decay pathways in Escherichia coli.

To define basic features of mRNA processing and decay in Escherichia coli, we have examined a set of mRNAs encoded by the filamentous phage f1 that have structures typical of bacterial mRNAs. They bear a stable hairpin stem-loop on the 3' end left from rho-independent termination and are known to undergo processing by RNase E. A small percentage of the f1 mRNAs were found to bear poly(A) tails that were attached to heterogeneous positions near the common 3' end.

Distinguishing schizophrenic patients from healthy controls by quantitative measurement of eye movement parameters.

Background: Eye tracking dysfunction is a putative trait marker for susceptibility to schizophrenia; however, it cannot be recommended as an additional tool for the diagnosis of schizophrenia, due to low sensitivity and specificity.

Methods: To assess the diagnostic potentials of combinations of eye movement paradigms, four smooth pursuit experiments (1: constant velocity of 15 degrees/sec; 2 and 3: combination with either visual or auditory distractors; 4: constant velocity of 30 degrees/sec) and two saccadic eye movement experiments (1: reflexive saccades; 2: voluntary saccades) were conducted. Fourteen patients with residual schizophrenia and 17 healthy controls were studied.

Appropriate expression of filamentous phage f1 DNA replication genes II and X requires RNase E-dependent processing and separate mRNAs.

The products of in-frame overlapping genes II and X carried by the filamentous phage f1 genome are proteins with required but opposing functions in phage DNA replication. Their normal relative levels are important for continuous production of phage DNA without killing infected Escherichia coli hosts. Here we identify several factors responsible for determining the relative levels of pII and pX and that, if perturbed, alter the normal distribution of the phage DNA species in infected hosts.

Translation limits synthesis of an assembly-initiating coat protein of filamentous phage IKe.

Translation is shown to be downregulated sharply between genes V and VII of IKe, a filamentous bacteriophage classed with the Ff group (phages f1, M13, and fd) but having only 55% DNA sequence identity to it. Genes V and VII encode the following proteins which are used in very different amounts: pV, used to coat the large number of viral DNA molecules prior to assembly, and pVII, used to serve as a cap with pIX in 3 to 5 copies on the end of the phage particle that emerges first from Escherichia coli. The genes are immediately adjacent to each other and are represented in the same amounts on the Ff and IKe mRNAs.

Filamentous phage IKe mRNAs conserve form and function despite divergence in regulatory elements.

As a means of determining whether there has been selection to conserve the basic pattern of filamentous phage mRNAs, the major mRNAs representing genes II to VIII have been defined for a phage distantly related to the Ff group specific for Escherichia coli hosts bearing F pili. Phage IKe has a genome with 55% identity with the Ff genome and infects E. coli strains bearing N pili.

Functional analysis of filamentous phage f1 mRNA processing sites.

The abundant mRNAs used as templates for synthesis of filamentous phage f1 proteins are a combination of primary transcripts and 3' products of processing. The processing steps are mediated by host endoribonucleases. One of the enzymes implicated in f1 mRNA processing is RNase E, the only endonuclease thus far shown to have a global role in mRNA decay.

[Disorders of eye movements in schizophrenia--a critical review and future perspectives].

Disorders of smooth pursuit eye movements and saccadic eye movements have been reported frequently in schizophrenics. Probably 50% of the schizophrenic probands and of their unaffected relatives perform abnormal smooth pursuit movements. These deficiencies have been regarded as a possible genetic trait marker for schizophrenic vulnerability.

Mutational analysis of an inherently defective translation initiation site.

In a reverse of many studies of translational initiation sites, we have explored the basis for the inactivity of an apparently defective initiation site. Gene VII of the filamentous phage f1 has a translational start site with highly unusual functional properties and a sequence dissimilar to a prokaryotic ribosome binding site. The VII site shows no activity in assays of independent initiation, even in a deletion series designed to remove potentially interfering RNA secondary structure.

Characterization of elongating T7 and SP6 RNA polymerases and their response to a roadblock generated by a site-specific DNA binding protein.

As a means of generating homogeneous populations of elongation complexes with the RNA polymerases encoded by phages T7 and SP6, transcription has been carried out in vitro on templates associated with the Gln-111 mutant of EcoRI endonuclease. The Gln-111 protein, as a result of a single amino acid substitution at position 111, lacks cleavage function yet shows higher than wild-type affinity for the EcoRI recognition sequence GAATTC. On a series of linear and circular templates associated with Gln-111 protein, blockage of the phage RNA polymerase elongation complex is observed.

Distinctive patterns of translational reinitiation in the lac repressor mRNA: bridging of long distances by out-of-frame translation and RNA secondary structure, effects of primary sequence.

In the early region of the Escherichia coli lac repressor mRNA, translational reinitiation events triggered by nonsense codons occur over long distances and in a distinctive pattern not explained by simple use of the next available initiator triplet. Defined fusions of the restart sites to the lacZ coding region have been used to explore the basis for these reinitiation patterns and to ask whether the sites can function in independent initiation at the 5' end of an mRNA. The results obtained confirm earlier indications that the restart sites may have little or no inherent capacity for binding free 30S ribosomes.

Phage fl mRNA processing in Escherichia coli: search for the upstream products of endonuclease cleavage, requirement for the product of the altered mRNA stability (ams) locus.

In Escherichia coli infected with the filamentous phage f1, a number of the polycistronic phage mRNA species are generated through post-transcriptional processing by host nuclease activity. In this paper we review experimental evidence assessing whether known RNases are involved in mediating these processing events, and we use S1 nuclease mapping methods to visualize putative upstream products of endonuclease cleavage. By examining f1 processing in a phage-infected host bearing a temperature-sensitive allele of the altered message stability locus (ams), we show that production of the major processed species requires a component of the host cell which functions in the messenger RNA decay process.

Elongation by Escherichia coli RNA polymerase is blocked in vitro by a site-specific DNA binding protein.

As a means of determining how elongating RNA polymerase responds to a protein in its path, transcription has been carried out in vitro with the purified Escherichia coli enzyme on templates associated with a sequence-specific DNA binding protein. The major RNA species generated is the length expected from RNA polymerase which has transcribed to the position of the bound protein and is unable to elongate further. The binding proteins used are two mutants of the EcoRI endonuclease which are defective in cleavage function but retain high affinity for the wild-type recognition sequence (Wright, D.

Recognition and cleavage signals for mRNA processing lie within local domains of the phage f1 RNA precursors.

In Escherichia coli infected with the filamentous phage f1, a number of the abundant phage mRNAs, species C-G, are products of post-transcriptional processing. The approach of cloning the phage sequences likely to include the processing signals in a plasmid under transcriptional control of the lambda PL promoter (Blumer, K. J.

Translation of phage f1 gene VII occurs from an inherently defective initiation site made functional by coupling.

Expression of the filamentous phage f1 gene VII is shown to be translationally coupled to that of the upstream gene V. Fusions of the gene VII initiation site to the lacZ coding region were used to determine that initiation at the VII site is completely dependent on the process of translation having proceeded up to a stop codon immediately upstream from the VII site. Coupled expression from the VII site was found to be inefficient, proportional to the level of upstream translation, and very sensitive to the distance from the functional upstream stop codon.

Bacteriophage lambda N gene leader RNA. RNA processing and translational initiation signals.

The positions of RNA processing events mediated by RNase III and of two ribosome binding sites have been defined in an in vitro transcript of 321 nucleotides initiated at the major leftward promoter (PL) of bacteriophage lambda. Purified RNase III makes two specific endonucleolytic cleavages in the transcript at points 88 and 197 nucleotides from the PL start. The positions of these cuts suggest a secondary structure for the RNase III recognition site which is similar to other RNase III sites in which double-stranded cleavage occurs.

Translational control of phage f1 gene expression by differential activities of the gene V, VII, IX and VIII initiation sites.

Phage-specific transcription and subsequent RNA processing in Escherichia coli infected with the filamentous phage (f1, M13, fd) generate a pool of abundant and relatively long-lived phage mRNA species encoding the four adjacent genes V, VII, IX and VIII. Yet the products of gene V and gene VIII are synthesized at much higher levels than the gene VII and gene IX proteins. To ask if the translational initiation sites heading these genes show corresponding differences in activity and/or functional properties, we have purified a number of the phage mRNAs from cells infected with f1 and examined them in in vitro initiation reactions.

lac repressor blocks in vivo transcription of lac control region DNA.

Transcription of the Escherichia coli lac repressor gene (lacI) in vivo produces monocistronic mRNAs with discrete 3' ends in the lac control region, although the DNA sequence of this region does not specify a strong termination signal of the traditional form. Direct analysis of lac transcripts was used to show that the DNA sequence alone does not provide the signal to end the repressor mRNA and to establish that of the proteins with specific binding sites on control region DNA only the lac repressor has a striking effect on the continuity of lacI gene transcription. RNAs with 3' ends in the control region sequence are major mRNA species produced from a repressor-bound template, reflecting as much as a 50-fold increase over their levels in the repressor's absence.

Functional analysis of lac repressor restart sites in translational initiation and reinitiation.

To define some of the features that influence ribosomal recognition of translational restart sites in the lac repressor mRNA, recombinant DNA methods have been used to construct lacI-Z fusions in which lacZ gene expression is dependent upon initiation or reinitiation within lacI mRNA sequences. Reinitiation efficiencies, as assessed by beta-galactosidase levels in strains bearing such plasmids, appear to be determined by at least three features of the RNA between the termination codon and reinitiation codon: the presence of competing out-of-frame AUG or GUG triplets, the distance between termination and reinitiation points, and the extent to which restart sequences remain accessible to ribosomes. While some of the restart sites are used with substantial efficiency for reinitiation, they do not function detectably as primary initiators if placed at the 5' end of the lacZ mRNA.

Messenger RNA conformation and ribosome selection of translational reinitiation sites in the lac repressor mRNA.

In the early region of the Escherichia coli lac repressor mRNA, the pattern of cleavage by nucleases specific for single or double-stranded RNA confirms the presence of secondary structures previously proposed to influence the pattern of translational reinitiation. These are positioned so as to mask a potential restart site centered on an in-phase GUG triplet corresponding to repressor amino acid position Val38. Our finding that a restart polypeptide initiated at the Val38 GUG codon is observed only in situations that that preclude base-pairing of adjacent mRNA sequences establishes a functional role for these structures in vivo.

mRNA processing in Escherichia coli: an activity encoded by the host processes bacteriophage f1 mRNAs.

To examine the regions of the male-specific filamentous bacteriophage f1 genome that include signals for mRNA processing, the 5' endpoints of the major in vivo phage mRNAs have been located in the f1 DNA sequence by S1 nuclease mapping. The 5' ends of the purified mRNAs and additional phage-specific RNAs transiently visible early after infection occur in clusters of T-rich residues within genes that code for three phage proteins. When a 270-nucleotide region encompassing the 5' endpoints of three processed RNAs is transcribed as part of the bacteriophage lambda N mRNA in uninfected female cells, RNA 5' ends identical to ends of the three f1 RNAs are generated from the lambda-f1 precursor.

Lac repressor mRNA transcription terminates in vivo in the lac control region.

We have isolated the in vivo messenger RNA encoding the lactose repressor protein of Escherichia coli by hybridization to lacI gene DNA, and have verified its identity by characterizing specific fragments derived from its 5' and 3' ends. The 3' end points of the RNA, as shown by oligonucleotide analysis and S1 nuclease-mapping data, are clustered in the lac control region, within 70 nucleotides beyond the end of the repressor protein coding sequence. DNA fragments from this region, when inserted between the E.