In this task, you are given an abstract of article. Your task is to generate title for this article. Preferred titles are under thirty words.

Ex Input:
The development of in vitro assays to analyze pre-mRNA splicing resulted in the discovery of many fundamental features characterizing splicing signals and the machinery that completes this process. Because in vitro assays can be manipulated by various biochemical approaches, the versatility of investigating alternative pre-mRNA splicing in the test tube appears endless. Importantly, modifications in reaction conditions can lead to the accumulation, isolation, and characterization of reaction intermediates, a prerequisite for gaining mechanistic insights into how the spliceosome carries out intron removal, and how regulatory elements assist the general splicing machinery in defining splice sites and alternative exons. These considerable experimental advantages have made the in vitro splicing system a standard assay, even though this approach is independent from RNA transcription and other RNA processing events, and in some respects deviates from the natural process of mRNA biogenesis. Here, we describe the tools and techniques necessary to carry out in vitro splicing assays. Analyses of various experimental designs are presented to highlight the approaches taken to gain insights into the mechanisms by which splice site recognition and activation are communicated with the general splicing machinery. Methods to measure the kinetics of splicing, to observe the formation of the pre-spliceosomal complexes, and to manipulate and modify the in vitro system to resolve the regulatory influences in alternative splicing are presented.

Ex Output:
Analyzing mechanisms of alternative pre-mRNA splicing using in vitro splicing assays.

Ex Input:
The three-dimensional structure of an HNF-3/fork head DNA-recognition motif complexed with DNA has been determined by X-ray crystallography at 2.5 A resolution. This / protein binds B-DNA as a monomer, through interactions with the DNA backbone and through both direct and water-mediated major and minor groove base contacts, inducing a 13 bend. The transcription factor fold is very similar to the structure of histone H5. In its amino-terminal half, three -helices adopt a compact structure that presents the third helix to the major groove. The remainder of the protein includes a twisted, antiparallel -structure and random coil that interacts with the minor groove.

Ex Output:
Co-crystal structure of the HNF-3/fork head DNA-recognition motif resembles histone H5

Ex Input:
This paper seeks to establish the strength of association between contemporary tuberculosis (TB) in England and Wales and several potential aetiological factors. It presents an ecological analysis of standardised annual TB mortality rates for the 403 local authority districts between 1982 and 1992, disaggregated by age and sex. Social, demographic and ethnicity measures from the 1981 and 1991 censuses and standardised annual AIDS-related mortality rates for young men are used to calculate Poisson regression models. A strong association was found between all TB mortality groups and overcrowding at the household level. For women, no other measures improved the explanatory power of the models. In multiple regressions, both poverty and AIDS-related mortality explained additional variation in the model for younger men. The link between ethnicity and tuberculosis notifications was not reflected in this analysis of mortality. For all groups no evidence of a positive relationship with ethnicity was found, once overcrowding had been accounted for. The significance of household as opposed to district level crowding suggests that prolonged contact is required for disease transmission. Regression analysis indicates that it is the overcrowding and poverty among ethnic populations that is significant for their tuberculosis mortality. The fact that the relationship between AIDS and TB is confined to the group most typical of AIDS patients provides evidence that AIDS has little influence on the level of tuberculosis mortality in the wider population. Explanations for the observed relationship include preferential certification, migration for treatment and shortcomings in health care provision.

Ex Output:
Tuberculosis mortality in England and Wales during 1982-1992: its association with poverty, ethnicity and AIDS.