NEKL-4 regulates microtubule stability and mitochondrial health in ciliated neurons.

Ciliopathies are often caused by defects in the ciliary microtubule core. Glutamylation is abundant in cilia, and its dysregulation may contribute to ciliopathies and neurodegeneration. Mutation of the deglutamylase CCP1 causes infantile-onset neurodegeneration. In C. elegans, ccpp-1 loss causes age-related ciliary degradation that is suppressed by a mutation in the conserved NEK10 homolog nekl-4. NEKL-4 is absent from cilia, yet it negatively regulates ciliary stability via an unknown, glutamylation-independent mechanism. We show that NEKL-4 was mitochondria-associated. Additionally, nekl-4 mutants had longer mitochondria, a higher baseline mitochondrial oxidation state, and suppressed ccpp-1∆ mutant lifespan extension in response to oxidative stress. A kinase-dead nekl-4(KD) mutant ectopically localized to ccpp-1∆ cilia and rescued degenerating microtubule doublet B-tubules. A nondegradable nekl-4(PEST∆) mutant resembled the ccpp-1∆ mutant with dye-filling defects and B-tubule breaks. The nekl-4(PEST∆) Dyf phenotype was suppressed by mutation in the depolymerizing kinesin-8 KLP-13/KIF19A. We conclude that NEKL-4 influences ciliary stability by activating ciliary kinesins and promoting mitochondrial homeostasis.

NEKL-4 regulates microtubule stability and mitochondrial health in C. elegans ciliated neurons.

Ciliopathies are often caused by defects in the ciliary microtubule core. Glutamylation is abundant in cilia, and its dysregulation may contribute to ciliopathies and neurodegeneration. Mutation of the deglutamylase CCP1 causes infantile-onset neurodegeneration. In C. elegans, ccpp-1 loss causes age-related ciliary degradation that is suppressed by mutation in the conserved NEK10 homolog nekl-4. NEKL-4 is absent from cilia, yet negatively regulates ciliary stability via an unknown, glutamylation-independent mechanism. We show that NEKL-4 was mitochondria-associated. nekl-4 mutants had longer mitochondria, a higher baseline mitochondrial oxidation state, and suppressed ccpp-1 mutant lifespan extension in response to oxidative stress. A kinase-dead nekl-4(KD) mutant ectopically localized to ccpp-1 cilia and rescued degenerating microtubule doublet B-tubules. A nondegradable nekl-4(PESTΔ) mutant resembled the ccpp-1 mutant with dye filling defects and B-tubule breaks. The nekl-4(PESTΔ) Dyf phenotype was suppressed by mutation in the depolymerizing kinesin-8 KLP-13/KIF19A. We conclude that NEKL-4 influences ciliary stability by activating ciliary kinesins and promoting mitochondrial homeostasis.

Cdc6 is sequentially regulated by PP2A-Cdc55, Cdc14, and Sic1 for origin licensing in S. cerevisiae.

Cdc6, a subunit of the pre-replicative complex (pre-RC), contains multiple regulatory cyclin-dependent kinase (Cdk1) consensus sites, SP or TP motifs. In Saccharomyces cerevisiae, Cdk1 phosphorylates Cdc6-T7 to recruit Cks1, the Cdk1 phospho-adaptor in S phase, for subsequent multisite phosphorylation and protein degradation. Cdc6 accumulates in mitosis and is tightly bound by Clb2 through N-terminal phosphorylation in order to prevent premature origin licensing and degradation. It has been extensively studied how Cdc6 phosphorylation is regulated by the cyclin-Cdk1 complex. However, a detailed mechanism on how Cdc6 phosphorylation is reversed by phosphatases has not been elucidated. Here, we show that PP2ACdc55 dephosphorylates Cdc6 N-terminal sites to release Clb2. Cdc14 dephosphorylates the C-terminal phospho-degron, leading to Cdc6 stabilization in mitosis. In addition, Cdk1 inhibitor Sic1 releases Clb2·Cdk1·Cks1 from Cdc6 to load Mcm2-7 on the chromatin upon mitotic exit. Thus, pre-RC assembly and origin licensing are promoted by phosphatases through the attenuation of distinct Cdk1-dependent Cdc6 inhibitory mechanisms.

Proteomic Tools for the Analysis of Cytoskeleton Proteins.

Proteomic analyses have become an essential part of the toolkit of the molecular biologist, given the widespread availability of genomic data and open source or freely accessible bioinformatics software. Tools are available for detecting homologous sequences, recognizing functional domains, and modeling the three-dimensional structure for any given protein sequence, as well as for predicting interactions with other proteins or macromolecules. Although a wealth of structural and functional information is available for many cytoskeletal proteins, with representatives spanning all of the major subfamilies, the majority of cytoskeletal proteins remain partially or totally uncharacterized. Moreover, bioinformatics tools provide a means for studying the effects of synthetic mutations or naturally occurring variants of these cytoskeletal proteins. This chapter discusses various freely available proteomic analysis tools, with a focus on in silico prediction of protein structure and function. The selected tools are notable for providing an easily accessible interface for the novice while retaining advanced functionality for more experienced computational biologists.

Reforma trabalhista e relações de trabalho no Brasil: por quem os sinos dobram? / Labor reform and labor relations in Brazil: for whom do the bells toll?

As reformas trabalhistas de 2017 são a mais abrangente alteração sofrida pela CLT desde seu lançamento. Este artigo compara as novas leis e o posicionamento sobre o tema por parte da CNI e do DIEESE, entidades que representam dois dos grupos sociais mais afetados: patrões industriais e trabalhadores. A partir do referencial da economia neoclássica e dos estudos de Dunlop sobre Sistemas de Relações Industriais, demonstra-se que a reforma atende diretamente aos interesses patronais, em detrimento dos pontos de vista colocados pela entidade dos trabalhadores, refletindo uma correlação de forças muito desfavorável a estes últimos, e lançando dúvidas sobre a capacidade explicativa dos sistemas "equilibrados" de Dunlop. O método consiste em apresentar as alterações na legislação, contrastando-as com o posicionamento das entidades. Verifica-se 100% de convergência entre as novas leis e a visão da CNI, com ampla rejeição por parte do DIEESE, o que indica a lógica por trás das reformas: a recomendação (neoclássica) de flexibilização do mercado de trabalho, argumento caro ao patronato, mas problematizado por vários estudos acadêmicos na área das relações de trabalho.

2017 labor reforms are the most far-reaching change Brazilian Labor Laws (CLT) has undergone since its launch. This article compares the new laws and the position on the subject by the CNI and DIEESE, entities which represent two of the most affected social groups: industrial bosses and workers. Based on the framework of neoclassical economics and Dunlop's studies on Industrial Relations Systems, it is demonstrated that the reform directly serves the employers' interests, to the detriment of points of view put forward by the workers' entity, reflecting a very unfavourable correlation of forces to the latter, and casting doubt on the explanatory power of Dunlop's "balanced" systems. The method consists of presenting changes in the legislation, contrasting them with the entities' positions. There is 100% convergence between the new laws and CNI's view on the matter, with broad rejection by DIEESE, which indicates the logic behind the reforms: the (neoclassical) recommendation for flexibility in the labor market, an argument that is dear to the bosses, but problematized by several academic studies in work relations field.

Individualization of controlled ovarian stimulation in vitro fertilization using markers of ovarian reserve: a systematic review / Individualização da estimulação ovariana controlada na fertilização in vitro com o uso de marcadores da reserva ovariana: uma revisão sistemática

Introduction: The main objective of individualization of treatment in IVF is to offer every single woman the best treatment tailored to her own unique characteristics, thus maximizing the chances of pregnancy and eliminating the iatrogenic and avoidable risks resulting from ovarian stimulation. Personalization of treatment in IVF should be based on the prediction of ovarian response. Objective: To summarize the predictive ability of ovarian reserve markers, and the therapeutic strategies that have been proposed in IVF after this prediction. Methods: A systematic review of the existing literature was performed by searching Medline, LILACS, SciELO and Pubmed, for publications related to ovarian reserve markers and their incorporation into controlled ovarian stimulation (COS) protocols in IVF. Results: 251 articles were found. Ten articles published between 2010 and 2015 were selected. Conclusion: Antral follicle count (AFC) and anti-Mullerian hormone (AMH), the most sensitive markers of ovarian reserve, are ideal in planning personalized COS protocols. These markers permit prediction of the ovarian response with reliable accuracy. Following the categorization of expected ovarian response clinicians can adopttailored therapeutic strategies for each patient.(AU)

Introdução: O principal objetivo da individualização do tratamento na fertilização in vitro é oferecer a cada mulher o melhor tratamento sob medida para suas próprias características únicas, maximizar, assim, as chances de gravidez e eliminar os riscos de iatrogenia durante a estimulação ovariana. A personalização do tratamento na fertilização in vitro deve basear-se na predição da resposta ovariana. Objetivo: Avaliar o uso de marcadores da reserva ovariana para individualização da dose inicial do FSH nos ciclos de FIV. Métodos: Revisão sistemática da literatura feita por meio de pesquisa Medline, Lilacs, SciELO e PubMed, para publicações relacionadas com marcadores reserva ovariana e sua incorporação, estimulação ovariana (COS) e protocolos controlados em fertilização in vitro. Resultados: Foram achados 251 artigos. Foram selecionados dez artigos publicados entre 2010 e 2015. Conclusão: Contagem de folículos antrais (AFC) e hormônio anti-Müulleriano (AMH), os marcadores mais sensíveis da reserva ovariana, são ideais no planejamento de protocolos individualizados. Esses marcadores permitem previsão da resposta ovariana com confiança De acordo com a resposta ovariana esperada, os clínicos podem adotar estratégias terapêuticas sob medida para cada paciente.(AU)