The SPF27 Homologue Num1 Connects Splicing and Kinesin 1-Dependent Cytoplasmic Trafficking in Ustilago maydis

The conserved NineTeen protein complex (NTC) is an integral subunit of the spliceosome and required for intron removal during pre-mRNA splicing. The complex associates with the spliceosome and participates in the regulation of conformational changes of core spliceosomal components, stabilizing RNA-RNA- as well as RNA-protein interactions. In addition, the NTC is involved in cell cycle checkpoint control, response to DNA damage, as well as formation and export of mRNP-particles. We have identified the Num1 protein as the homologue of SPF27, one of NTC core components, in the basidiomycetous fungus Ustilago maydis. Num1 is required for polarized growth of the fungal hyphae, and, in line with the described NTC functions, the num1 mutation affects the cell cycle and cell division. The num1 deletion influences splicing in U. maydis on a global scale, as RNA-Seq analysis revealed increased intron retention rates. Surprisingly, we identified in a screen for Num1 interacting proteins not only NTC core components as Prp19 and Cef1, but several proteins with putative functions during vesicle-mediated transport processes. Among others, Num1 interacts with the motor protein Kin1 in the cytoplasm. Similar phenotypes with respect to filamentous and polar growth, vacuolar morphology, as well as the motility of early endosomes corroborate the genetic interaction between Num1 and Kin1. Our data implicate a previously unidentified connection between a component of the splicing machinery and cytoplasmic transport processes. As the num1 deletion also affects cytoplasmic mRNA transport, the protein may constitute a novel functional interconnection between the two disparate processes of splicing and trafficking

The Emergence and Survival of \u3cem\u3eDigitaria eriantha\u3c/em\u3e and \u3cem\u3eChloris gayana\u3c/em\u3e Seedlings on Mine Tailings Planted with Coated and Non-Coated Seed

The importance of vegetation in the process of rehabilitation and stabilisation of mined land is becoming more critical as the size of the affected areas and the impact on urban development increases. Successful establishment of vegetation on these areas are complicated by adverse physical and chemical properties of the growth mediums. These include; soil compaction, acidity, salinity and heavy metal contamination, extreme temperatures, low soil water contents and soil erosion (Oncel et al. 2000; Turner et al. 2006; Aken et al. 2007). Many of these soil/substrate conditions mentioned limit the establishment of vegetation from seed. Seed coating technologies have become a possible solution to address difficult seeding challenges to ultimately facilitate more successful establishment of vegetation in these hostile environments (Turner et al. 2006). From humble beginnings seed coating has developed into technologies that can be used to ameliorate the root zone to an extent by chemically changing the environment, aerating the root zone or by improving the seedlings health through the inoculation of seedling environment with beneficial micro-organisms (Harman 1991; Thrall et al. 2005; Turner et al. 2006). These specific attributes are not always clear and environmental specialists do not always know they have access to technologies that can change the micro-environment of a seedling

Bayesian model-based age classification using small mammal body mass and capture dates

Accurate age determination is a fundamental prerequisite for demographic studies as well as population monitoring efforts that provide information for management and conservation. Yet, common age determination methods suffer from low accuracy rates, impose additional handling and time costs on animals and biologists, or rely on invasive techniques such as tooth extraction. We introduce an alternative, mixture modeling approach for age determination that exploits mammalian growth patterns to classify newly encountered animals as juveniles or adults, and present an example analysis that classifies Allegheny woodrats based solely on their capture dates and mass at capture, in combination with data from known adults. We also introduce and validate a simulation-based heuristic to evaluate potential classification accuracy when no known-age test cases are available. In the Allegheny woodrat example, the mixture model achieved a 90–92% accuracy rate (heuristic range: 89–94%), far better than the 36–43% achieved with a fixed mass criterion, and comparable to accuracies reported for other species using more data-intensive, multivariate classification techniques. The model can be extended to classify multiple age groups, estimate chronological age, or further improve accuracy by including additional morphometric measures

Descrição da série caudal de um titanosaurídeo do Grupo Bauru, Cretáceo Superior do Brasil

A new titanosaurid, Baurutitan britoi n. gen., n. sp., is described and compared with other taxa of that sauropod clade. The specimen (MCT 1490-R) consists of the last sacral followed by a sequence of 18 caudal vertebrae that were found in the continental deposits of the Late Cretaceous Bauru Group that outcrop at the Peirópolis region, near the town of Uberaba, State of Minas Gerais, Brazil. This new taxon is distinguished from other titanosaurians by several features, including subrectangular to square outline of the anterior articulation surface of the anterior and middle caudals, strongly pointed laterally directed process intercepting the spinoprezygapophyseal lamina in caudal 1; dorsal prezygapophyseal tuberosity on the lateral margin of the prezygapophyses of caudals 2-4, that smoothens out in midcaudals. This material demonstrates that the horizontal ridge present in middle and posterior caudals of some titanosaurs, inBaurutitan britoi is homologous with a dorsal tuberosity and not with the transverse process.Um novo titanossaurídeo, Baurutitan britoi n. gen., n. sp., é descrito e comparado com outros membros desse clado de saurópodes. O espécime é composto por uma última vértebra sacral seguida de uma seqüência de 18 vértebras caudais (MCT 1490-R) proveniente das cercanias do povoado de Peirópolis, no Município de Uberaba (Estado de Minas Gerais, Brasil), tendo sido encontrado nos depósitos continentais do Grupo Bauru (Cretáceo Superior). Entre as características que distinguem esse novo táxon dos demais Titanosauria estão a face subretangular ou quadrada da articulação anterior das caudais, processo lateral bem desenvolvido interceptando a lamina espinopré-zigapofisiária da caudal 1, tubérculo dorsal na margem lateral das pré-zigapófises das caudais 2-4, que se torna em uma rugosidade que tende a se tornar menos pronunciada nas caudais médias. Este material também demonstra que em Baurutitan britoi n. gen., n. sp. a crista lateral nos centros das caudais medianas é o resultado de uma diminuição de um processo dorsal e não é homólogo do processo transverso

NAIL-MS reveals the repair of 2-methylthiocytidine by AlkB in E. coli

RNAs contain post-transcriptional modifications, which fulfill a variety of functions in translation, secondary structure stabilization and cellular stress survival. Here, 2-methylthiocytidine (ms(2)C) is identified in tRNA of E. coli and P. aeruginosa using NAIL-MS (nucleic acid isotope labeling coupled mass spectrometry) in combination with genetic screening experiments. ms(2)C is only found in 2-thiocytidine (s(2)C) containing tRNAs, namely tRNA(CCG)(Arg), tRNA(ICG)(Ar)(g), tRNA(UCU)(Arg) and tRNA(GCU)(Ser )at low abundances. ms(2)C is not formed by, commonly known tRNA methyltransferases. Instead, we observe its formation in vitro and in vivo during exposure to methylating agents. More than half of the s(2)C containing tRNA can be methylated to carry ms(2)C. With a pulse-chase NAIL-MS experiment, the repair mechanism by AlkB dependent sulfur demethylation is demonstrated in vivo. Overall, we describe ms(2)C as a bacterial tRNA modification and damage product. Its repair by AlkB and other pathways is demonstrated in vivo by our powerful NAIL-MS approach

An attempt to optimize the outcome of penetrating keratoplasty in congenital aniridia-associated keratopathy (AAK)

Purpose To propose an optimized microsurgical and medical approach to reduce the risk of complications after penetrating keratoplasty (PKP) in patients with aniridia-associated keratopathy (AAK). Methods Retrospective observational case series of 25 PKP performed in 16 patients with AAK. Preoperative indications were endothelial decompensation and vascularized scars (68%) or graft failure (32%) due to limbal stem cell deficiency. The optimized approach included a combination of a small corneal graft size (around 7.0 mm), interrupted 10–0nylon sutures, simultaneous AMT as a patch, large bandage contact lens, temporary lateral tarsorrhaphy, postoperative autologous serum eye drops, and systemic immunosuppression. Main outcome measures included: visual acuity, transplant survival, and complications encountered during follow-up of 107 weeks on average. Results A complete modified keratoplasty scheme was used in 10 of 25 PKP (group 1), while at least one of the modifications was missing in the other 15 PKP (group 2). After 8 weeks of follow-up, the epithelium was closed in 23 eyes. Visual acuity improved in 19 eyes at 6 months of follow-up, and remained stable in six eyes. None of the eyes showed a decrease in visual acuity. At the last post-operative follow-up, this visual improvement persisted in 14 eyes and graft survival rate after 156 weeks (3 years) was 69% in group 1 versus 44% in group 2 (p = 0.39, log-rank test). Secondary corneal neovascularization (8%), scarring (4%), ulcer (4%), or graft rejection (8%) happened mostly in the second group which was missing at least one of the suggested modifications. Conclusions PKP in congenital aniridia must be considered as a high-risk keratoplasty. An optimized therapeutic approach seems to be promising in order to reduce the postoperative complication rate in these most difficult eyes