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We found that mammalian Polycomb group (PcG) protein YY1 can bind to Polycomb response elements in Drosophila embryos and can recruit other PcG proteins to DNA. PcG recruitment results in deacetylation and methylation of histone H3. In a CtBP mutant background, recruitment of PcG proteins and concomitant histone modifications do not occur. Surprisingly, YY1 DNA binding in vivo is also ablated. CtBP mutation does not result in YY1 degradation or transport from the nucleus, suggesting a mechanism whereby YY1 DNA binding ability is masked. These results reveal a new role for CtBP in controlling YY1 DNA binding and recruitment of PcG proteins to DNA.

The presence of one or more TATATAA motifs in the flanking sequences of individual members of a multi-gene tRNA(Gly)(1) family from the mulberry silkworm, Bombyx mori, negatively modulated the transcription of the gene copies. Characterization of proteins from posterior silk gland nuclear extracts, binding to the TATATAA motif, identified a novel 43 kD protein, designated here as P43 TATA-box-binding factor (TBF). The protein was purified to homogeneity. P43 TBF binding was highly sequence-specific and showed a 100-fold-higher affinity for binding than the TATA-box-binding protein (TBP). The protein also showed binding to the TATAAA sequence of the actin5C promoter. P43 TBF inhibited transcription of all the tRNA genes examined, as well as RNA polymerase II transcription from the actin5C promoter. The amino acid sequence of eleven peptides generated from P43 TBF did not share homology with proteins that bind the TATA box, such as TBP, TRF (TBP-related factor) or TLFs (TBP-like factors) reported from other sources. Inhibition of transcription of tRNA genes by P43 TBF could not be reversed by TBP. The inhibitory effect appeared to be exerted through sequestration of the associated transcription factors.

Fractionation of nuclear extracts from posterior silk glands of mulberry silkworm Bombyx mori, resolved the transcription factor TFIIIC into two components (designated here as TFIIIC and TFIIIC1) as in HeLa cell nuclear extracts. The reconstituted transcription of tRNA genes required the presence of both components. The affinity purified TFIIIC is a heteromeric complex comprising of five subunits ranging from 44 to 240 kDa. Of these, the 51-kDa subunit could be specifically crosslinked to the B box of tRNA1Gly. Purified swTFIIIC binds to the B box sequences with an affinity in the same range as of yTFIIIC or hTFIIIC2. Although an histone acetyl transferase (HAT) activity was associated with the TFIIIC fractions during the initial stages of purification, the HAT activity, unlike the human TFIIIC preparations, was separated at the final DNA affinity step. The tRNA transcription from DNA template was independent of HAT activity but the repressed transcription from chromatin template could be partially restored by external supplementation of the dissociated HAT activity. This is the first report on the purification and characterization of TFIIIC from insect systems.

This study describes the profile and nature of social disabilities in schizophrenia and the effect of intervention on them. Sixty five schizophrenic patients who constituted the experimental group were compared with sixty patients from a different centre. They were evaluated at intake for negative symptoms, social disabilities and psychological impairments. One group was provided with medication alone and the other was exposed to an intervention programme comprising of social skills training, family education, occupational therapy and medication management training, etc. After one year, both the groups were evaluated on the same parameters. It was found that both groups showed decline in some negative symptoms and improvement in certain disabilities. Issues such as duration of intervention, components of intervention and role of psychosocial rehabilitation are discussed.

The family is a major source of support for the mentally ill in India. Although Indian families show tremendous resilience in caring for their ill relatives, they experience a lot of physical and emotional distress. The burden assessment schedule (BAS) aims to assess both objective and subjective burden experienced by the primary care givers of chronic mentally ill patients. Stepwise ethnographic exploration has been used in the development of this 40 item instrument. Reliability exercises have been carried out throughout the development of this schedule. Criterion validity has been established by comparing with another standardized instrument to assess burden, which has been developed in India.

The responses to supplementing the diet of Single Comb White Leghorn (SCWL) cockerels with ethoxyquin were tested on two parameters: 1) tissue peroxidation and 2) immune response. In the first experiment, three concentrations of supplemental ethoxyquin (0, 500, and 1,000 ppm) were added to a basal diet and fed to SCWL cockerels for 6 wk. Tissue peroxidation was assessed by measuring the thiobarbituric acid reactive substances (TBARS) concentration in the liver, kidney, heart, and spleen. The TBARS concentration in response to 500 ppm dietary ethoxyquin was significantly lower in the liver and spleen tissues, whereas in the kidneys, 1,000 ppm ethoxyquin significantly lowered TBARS. In a second experiment, four concentrations of ethoxyquin (0, 125, 500, and 1,000 ppm) were added to a basal diet and fed to SCWL cockerels for 8 wk. The primary and secondary immune response were assessed by determining antibody titers to the Newcastle disease virus using hemagglutination inhibition (HI) and ELISA. The HI and ELISA titers for the primary and secondary immune response were not significantly different from the control. Analysis of body weight, feed conversion, and organ weight revealed no statistically significant differences between treatments, although in the second experiment the dietary treatment of 1,000 ppm ethoxyquin resulted in significantly higher relative liver weight.

Several instruments measuring social functioning have been developed in the last four decades, as a result of the increasing interest in community care of the chronic mentally ill. SCARF Social Functioning Index (SSFI) was developed to meet the pressing need for an instrument which was easy to administer and which could be used by all mental health professionals. The SSFI comprises four main sections: self concern, occupational role, role in the family and other social roles. Each section has several subsections covering different areas of social functioning. Validity and reliability have been established for a group of normals, patients suffering from schizophrenia and from Hansen's disease. Internal consistencies of these factors were high Factor analysis derived four main factors, which included nearly all items of the SSFI. This paper reports on the development and standardization of the instrument.