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Alzheimer's disease (AD) is considered to be a conformational disease arising from the accumulation of misfolded and unfolded proteins in the endoplasmic reticulum (ER). SEL1L is a component of the ER stress degradation system, which serves to remove unfolded proteins by retrograde degradation using the ubiquitin-proteosome system. In order to identify genetic variations possibly involved in the disease, we analysed the entire SEL1L gene sequence in Italian sporadic AD patients. Here we report on the identification of a new polymorphism within the SEL1L intron 3 (IVS3-88 A>G), which contains potential binding sites for transcription factors involved in ER-induced stress. Our statistical analysis shows a possible role of the novel polymorphism as independent susceptibility factor of Alzheimer's dementia. (C) 2005 Published by Elsevier Ireland Ltd.

CTLA4 protein is a receptor molecule that plays a critical role as a negative regulator of the immune response. Therefore, genetic variations in CTLA4 may confer susceptibility to autoimmune diseases such as multiple sclerosis (MS). In order to investigate the association of two CTLA4 polymorphisms (+49 A/G and -318 C/T) with multiple sclerosis, sporadic MS patients and healthy controls from Italy were genotyped through direct DNA sequencing. Considering single-loci variations, no differences in the allelic and genotypic frequencies between patients and controls were found. However, considering a putative interaction at the two loci, the T/G combination was more frequently observed in patients than in controls. This result suggests that this allelic combination of the CTLA4 polymorphisms may be involved in the susceptibility to MS in the Italian population.

The maize seed comprises two major compartments, the embryo and the endosperm, both originating from the double fertilization event. The embryogenetic process allows the formation of a well-differentiated embryonic axis, surrounded by a single massive cotyledon, the scutellum. The mature endosperm constitutes the bulk of the seed and comprises specific regions containing reserve proteins, complex carbohydrates, and oils. To gain more insight into molecular events that underlie seed development, three monogenic mutants were characterized, referred to as emp (empty pericarp) on the basis of their extreme endosperm reduction, first recognizable at about 12 d after pollination. Their histological analysis reveals a partial development of the endosperm domains as well as loss of adhesion between pedicel tissues and the basal transfer layer. In the endosperm, programmed cell death (PCD) is delayed. The embryo appears retarded in its growth, but not impaired in its morphogenesis. The mutants can be rescued by culturing immature embryos, even though the seedlings appear retarded in their growth. The analysis of seeds with discordant embryo-endosperm phenotype (mutant embryo, normal endosperm and vice-versa), obtained using B-A translocations, suggests that emp expression in the embryo is necessary, but not sufficient, for proper seed development. In all three mutants the picture emerging is one of a general delay in processes related to growth, as a result of a mutation affecting endosperm development as a primary event.