Conserved sequences in the β subunit of archaeal and eukaryal translation initiation factor 2 (elF2), absent from elF5, mediate interaction with elF2γ

The eukaryotic translation initiation factor 2 (eIF2) binds the methionyl-initiator tRNA in a GTP-dependent mode. This complex associates with the 40 S ribosomal particle, which then, with the aid of other factors, binds to the 5' end of the mRNA and migrates to the first AUG codon, where eIF5 promotes GTP hydrolysis, followed by the formation of the 80 S ribosome. Here we provide a comparative sequence analysis of the β subunit of eIF2 and its archaeal counterpart (aIF2β). aIF2β differs from eIF2β in not possessing an N-terminal extension implicated in binding RNA, eIF5 and eIF2B. The remaining sequences are highly conserved, and are shared with eIF5. Previously isolated mutations in the yeast eIF2β, which allow initiation of translation at UUG codons due to the uncovering of an intrinsic GTPase activity in eIF2, involve residues that are conserved in aIF2β, but not in eIF5. We show that the sequence of eIF2B homologous to aIF2β is sufficient for binding eIF2γ, the only subunit with which it interacts, and comprises, at the most, 78 residues, eIF5 does not interact with eIF2γ, despite its similarity with eIF2β, probably because of a gap in homology in this region. These observations have implications for the evolution of the mechanism of translation initiation.

Results of prostate cancer screening in non-symptomatic men

Objectives: To verify prostate cancer prevalence in non-symptomatic men between 50 and 70 years old as well as cancer characteristics. Material and Methods: 2815 non-symptomatic men had total PSA and digital rectal examination performed between March 1998 and April 1998. Racial distribution was: 2331 Caucasians (83.9%), 373 Blacks (13.4%) and 75 Asiatic (2.7%). PSA was normal in 2554 (91.4%), 4 to 10 in 177 (6.3%) and greater than 10 in 64 (2.3%). DRE was normal in 2419 (86.3%), suspicious in 347 (12.4%) and characteristic for cancer in 37 (1.3%). Men with abnormal DRE and/or PSA had transrectal prostate biopsy indicated. Results: 461 biopsies were done and 78 tumors was detected (prevalence = 2.8%). Prevalence was progressively higher with age (p < 0.001), PSA level (p < 0.0001) and DRE findings (p = 0.0216). Cancer prevalence in Blacks was 1.65 times higher than in Caucasians (p > 0.05) and 94.9% of detected tumors were moderately or poorly differentiated. Sensibility, specificity, positive predictive value, negative predictive value and total accuracy for PSA were respectively: 66.6%; 89.7%; 51.7%; 94.2% and 86.5%. For DRE, the respective values were: 49.1%; 79.4%; 50.9%; 78.3% and 70.3%. Conclusions: prostate cancer prevalence in the studied population (2.8%) was similar to that of other countries populations. Cancer prevalence in blacks was 1.65 times higher than in Caucasians (difference was not statistically significant). Cancer prevalence becomes higher with aging. The association of DRE and PSA is of paramount importance for cancer diagnosis. The great majority of detected tumors (94.9%) was moderately and poorly differentiated. Brazil probably needs regional studies to better characterize prostate cancer epidemiology due to population heterogeneity.

Comportamento ingestivo de cordeiros alimentados com dietas contendo feno de amoreira

The experiment was conducted to evaluate the feeding behavior of lambs fed with diets containing 0, 12.5 and 25.0% of mulberry hay as a substitute for the concentrate. Twenty four Ile de France lambs, non castrated, with 25 kg of body weight and four months old, confined, in a completely randomized design, were used. The feeding daily time (242.01 minutes), rumination (435.48 minutes) and leisure (762.50 minutes), the numbers of cakes ruminated per day (658.36) and the time spent per cake (40.03 sec) were not affected (P>0.05) by different levels of hay in mulberry concentrate. The dry matter voluntary intake (1.258 kg/day) and neutral detergent fiber intake (0.302 kg/day), as well as the efficiency of dry matter intake and rumination (316.24 and 173.54 g/h, respectively) and efficiency of neutral detergent fiber intake and rumination (75.89 and 41.68 g/h, respectively) were similar in all treatments. The ruminating chew expressed in hour/day (11.29) and the number of chews expressed per cake (72.65) and per day (47.638.06), as well as the number and the feeding time (22.02 meals and 11.23 min/meal), rumination (25.95 ruminations and 17.29 min/rumination) and idle (41.81 idle and 18.30 min/idle time), were also not affected (P>0.05). The inclusion of mulberry hay did not change the rumination expressed in g of DM and NDF/cake (1.91 and 0.46, respectively) and min/kg of DM and NDF (361.51 and 1.505.78, respectively), as well as the total chew expressed in min/kg of DM and NDF (563.70 and 2.347.19, respectively). The use of mulberry hay partially replacing the concentrated, does not change the feeding behavior of feedlot lambs.

Crescimento inicial de mudas de maracujazeiro amarelo em função de doses crescentes de superfosfato simples

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Unesp Informa, 2016, número 78

Boletim elaborado pela Assessoria de Comunicação e Imprensa da Reitoria da UNESP