The highly diverse TATA box-binding proteins among protists: A review.

Transcription is the first step of gene expression regulation and is a fundamental mechanism for establishing the viability and development of a cell. The TATA box-binding protein (TBP) interaction with a TATA box in a promoter is one of the best studied mechanisms in transcription initiation. TBP is a transcription factor that is highly conserved from archaea to humans and is essential for the transcription initiated by each of the three RNA polymerases. In addition, the discovery of TBP-related factor 1 (TRF1) and other factors related to TBP shed light on the variability among transcription initiation complexes, thus demonstrating that the compositions of these complexes are, in fact, more complicated than originally believed. Despite these facts, the majority of studies on transcription have been performed on animal, plant and fungal cells, which serve as canonical models, and information regarding protist cells is relatively scarce. The aim of this work is to review the diversity of the TBPs that have been documented in protists and describe some of the specific features that differentiate them from their counterparts in higher eukaryotes.

An in vitro characterisation of the Trichomonas vaginalis TATA box-binding proteins (TBPs).

The protozoan parasite Trichomonas vaginalis is a common human pathogen from one of the earliest-diverging eukaryotic lineages. At the transcriptional level, the highly conserved Inr element of RNA pol II-transcribed genes surrounds the transcription start site and is recognised by IBP39, a protein exclusive of T. vaginalis. Typical TATA boxes have not been identified in this organism but, in contrast, BLAST analyses of the T. vaginalis genome identified two genes encoding putative TATA-binding proteins (herein referred to as TvTBP1 and TvTBP2). The goal of this work was to characterise these two proteins at the molecular level. Our results show that both TvTBPs theoretically adopt the saddle-shaped structure distinctive to TBPs and both Tvtbp genes are expressed in T. vaginalis. TvTBP1 did not complement a Saccharomyces cerevisiae mutant lacking TBP; however, TvTBP1 and TvTBP2 proteins bound T. vaginalis DNA promoter sequences in EMSA assays. We propose that TvTBP1 may be part of the preinitiation transcription complex in T. vaginalis since TvTBP1 recombinant protein was able to bind IBP39 in vitro. This work represents the first approach towards the characterisation of general transcription factors in this early divergent organism.

[Development of an instrument to assess cultural beliefs about physicians]. / Identificación y medición de creencias culturales sobre los médicos: construcción y validación de un instrumento.

BACKGROUND: Beliefs about professionals' healthcare may influence healthcare behaviors. Such beliefs are in part the result of the interactions that professionals have with their patients. Recent studies highlight the importance of beliefs about physicians, their effect on health-care behaviors, and the requirement of culturally appropriate tools to measure such beliefs. AIM: To develop and validate a culturally appropriate instrument to measure beliefs about physicians. MATERIAL AND METHODS: Based on a "bottom-up" methodology, a culturally pertinent scale of beliefs about physicians was developed and then validated by expert judges. The resulting scale, with 26 items, was applied to 337 participants aged 31 ± 7 years (85% women). RESULTS: Two factors, grouping 24 items, emerged from the exploratory factor analysis. The first was called negative beliefs about doctors (Cronbach's α = 0.96) and the second was called positive beliefs about doctors (Cronbach's α = 0.95). Both factors explain 70 % of the scale variance. CONCLUSIONS: The devised instrument has adequate psychometric properties and is also culturally relevant. It allows the assessment of cultural beliefs about physicians.

Identificación y medición de creencias culturales sobre los médicos: construcción y validación de un instrumento / Development of an instrument to assess cultural beliefs about physicians

Background: Beliefs about professionals' healthcare may influence healthcare behaviors. Such beliefs are in part the result of the interactions that professionals have with their patients. Recent studies highlight the importance of beliefs about physicians, their effect on health-care behaviors, and the requirement of culturally appropriate tools to measure such beliefs. Aim: To develop and validate a culturally appropriate instrument to measure beliefs about physicians. Material and Methods: Based on a "bottom-up" methodology, a culturally pertinent scale of beliefs about physicians was developed and then validated by expert judges. The resulting scale, with 26 items, was applied to 337 participants aged 31 ± 7 years (85% women). Results: Two factors, grouping 24 items, emerged from the exploratory factor analysis. The first was called negative beliefs about doctors (Cronbach's α = 0.96) and the second was called positive beliefs about doctors (Cronbach's α = 0.95). Both factors explain 70 % of the scale variance. Conclusions: The devised instrument has adequate psychometric properties and is also culturally relevant. It allows the assessment of cultural beliefs about physicians.