An Update on Plant Photobiology and Implications for Cannabis Production

This review presents recent developments in plant photobiology and lighting systems for horticultural crops, as well as potential applications for cannabis (Cannabis sativa and C. indica) plant production. The legal and commercial production of the cannabis plant is a relatively new, rapidly growing, and highly profitable industry in Europe and North America. However, more knowledge transfer from plant studies and horticultural communities to commercial cannabis plant growers is needed. Plant photosynthesis and photomorphogenesis are influenced by light wavelength, intensity, and photoperiod via plant photoreceptors that sense light and control plant growth. Further, light properties play a critical role in plant vegetative growth and reproductive (flowering) developmental stages, as well as in biomass, secondary metabolite synthesis, and accumulation. Advantages and disadvantages of widespread greenhouse lighting systems that use high pressure sodium lamps or light emitting diode (LED) lighting are known. Some artificial plant lighting practices will require improvements for cannabis production. By manipulating LED light spectra and stimulating specific plant photoreceptors, it may be possible to minimize operation costs while maximizing cannabis biomass and cannabinoid yield, including tetrahydrocannabinol (or Δ9-tetrahydrocannabinol) and cannabidiol for medicinal and recreational purposes. The basics of plant photobiology (photosynthesis and photomorphogenesis) and electrical lighting systems are discussed, with an emphasis on how the light spectrum and lighting strategies could influence cannabis production and secondary compound accumulation

lincRNAs act in the circuitry controlling pluripotency and differentiation

Although thousands of large intergenic non-coding RNAs (lincRNAs) have been identified in mammals, few have been functionally characterized, leading to debate about their biological role. To address this, we performed loss-of-function studies on most lincRNAs expressed in mouse embryonic stem (ES) cells and characterized the effects on gene expression. Here we show that knockdown of lincRNAs has major consequences on gene expression patterns, comparable to knockdown of well-known ES cell regulators. Notably, lincRNAs primarily affect gene expression in trans. Knockdown of dozens of lincRNAs causes either exit from the pluripotent state or upregulation of lineage commitment programs. We integrate lincRNAs into the molecular circuitry of ES cells and show that lincRNA genes are regulated by key transcription factors and that lincRNA transcripts bind to multiple chromatin regulatory proteins to affect shared gene expression programs. Together, the results demonstrate that lincRNAs have key roles in the circuitry controlling ES cell state.Broad InstituteHarvard UniversityNational Human Genome Research Institute (U.S.)Merkin Family Foundation for Stem Cell Researc

Quelques aspects de l’influence religieuse sur le droit de la personne et de la famille au Québec

L’église, surtout l’Église catholique, a exercé au Québec une influence primordiale sur l’ensemble de nos institutions et notamment sur le droit civil. Cette influence s’est manifestée dès l’origine au Québec où s’appliquaient, en matière d’état civil et de mariage, les ordonnances royales françaises ayant leur source dans le droit canon. Après la cession du Canada à l’Angleterre, en 1760, les règles juridiques françaises relatives à l’état civil et au mariage, de même que celles qu’établissait la loi anglaise de 1795 sur la tenue des registres de l’état civil, ont été codifiées dans le premier Code civil de 1866. Ce Code civil fait des ministres des différentes congrégations religieuses des fonctionnaires de l’état civil, chargés de la garde et de la tenue des registres. Ce Code n’institue que le mariage religieux et renvoie aux empêchements religieux au mariage établis par les diverses sociétés religieuses, notamment ceux du droit canon. Il consacre le principe de l’indissolubilité du lien matrimonial. Le nouveau Code civil du Québec portant réforme du droit de la famille supprime ces empêchements religieux, reconnaît le mariage à la fois religieux et civil et établit la règle de la dissolution du mariage par le divorce. Une proposition législative portant réforme du droit des personnes a pour effet de séculariser le système d’enregistrement des actes de l’état civil par la mise sur pied d’un système administré par l’État. Ce nouveau Code civil, adopté par étapes, indique la décroissance de l’influence religieuse sur le droit civil. Il se fonde sur les principes fondamentaux de liberté et d’égalité, principes établis dans la Charte des droits et libertés de la personne du Québec.The Church, especially the Roman Catholic Church, has had an overwhelming influence on all Québec's institutions, and its civil law in particular. This influence can be traced to Québec's earliest days, when French royal edicts based on canon law were applied to marriage and marital status. After Canada was ceded to Britain in 1760, French legal rules regarding marriage and marital status, together with the provisions of the British Act of 1795 governing registration of vital statistics, were codified in the first Civil Code of 1866. Under this Code, the ministers of every religious congregation are officials responsible to the secular arm for keeping and maintaining records. The Code provides only for religious marriage, and refers to the religious obstacles to marriage laid down by the various religious bodies, and in particular to canon law. It enshrines the principle that the marriage bond is indissoluble. Québec's new Civil Code, in reforming family law, does away with these religious obstacles, recognizes both civil and religious marriage and lays down the rule that marriage can be dissolved by divorce. Proposed legislation to reform law of persons would secularize the system of registering vital statistics by creating a system to be administered by the government. This new Civil Code, which is being adopted in stages, points to the decline of religious influence over civil law. It is based on the fundamental principles of liberty and equality set forth in the Québec Charter of Human Rights and Freedoms

Identification of binding partners for the caspase-7 exosite

Les caspases forment une famille de protéases à cystéine impliquées dans plusieurs types de mort cellulaire programmée, comme l’apoptose, une mort cellulaire essentielle au maintien de l’homéostasie du corps permettant, entre autres, le remplacement d’une cellule défectueuse par une nouvelle en seulement quelques heures. Les caspase-3 et -7 sont les caspases principalement responsables de l’exécution de l’apoptose; la caspase-3 étant perçue comme la principale en raison de son activité intrinsèque plus élevée. Cependant, la caspase- 7 semble avoir un rôle plus spécialisé puisqu’elle clive plus efficacement certains substrats grâce à un exosite. Un exosite est un domaine de liaison supplémentaire se trouvant à l’extérieur de la pochette catalytique de l’enzyme. L’exosite de la caspase-7 est constitué principalement de quatre résidus lysine (K38KKK) formant une région chargée positivement qui lui permet de lier les substrats PARP-1 et p23 afin d’augmenter l’efficacité de clivage. Notre hypothèse est donc que l’exosite de la caspase-7 permette de lier différentes structures ou protéines dans la cellule. Notre but était donc d’identifier certains substrats de la caspase- 7 qui interagissent avec son exosite. Pour se faire, nous avons testé et optimisé cinq approches de spectrométrie de masse. Sur les cinq, deux approches nous ont permis d’identifier des substrats potentiels de la caspase-7. La première approche consistait en un clivage in vitro d’extraits cellulaires marqués à l’aide d’isotopes (SILAC) suivi d’une analyse en spectrométrie de masse de type shotgun et nous a permis d’établir une liste de protéines interagissant potentiellement avec l’exosite de la caspase-7. Certaines cibles prometteuses ont ensuite été validées. Nous avons confirmé que la Thymidylate synthase (TYMS) est clivée par la caspase-3, mais ne semble pas l’être par la caspase-7. Le récepteur du facteur de croissance fibroblastique (FGFR1) semble être clivé par les caspases, mais nous n’avons pas pu le valider avec certitude. Puisque cette approche n’a pas permis l’identification de nouveaux substrats de la caspase-7, une autre méthode a été établie qui consistait en un clivage in cellulo dans des cellules apoptotiques suivi d’un enrichissement des produits de clivage par la procédure TAILS et une analyse en spectrométrie de masse. Cette méthode a permis d’identifier dix protéines potentiellement clivées plus efficacement par la caspase-7. Enfin, basé sur des évidences provenant de la littérature, nous avons également tenté de confirmer si certains isoformes de la Protéine kinase C (PKC) clivés par la caspase-7 pouvaient interagir avec son exosite, mais sans succès. Notre hypothèse reste toujours à confirmer, par contre, l’étude des rôles cellulaires de ces substrats potentiels pourra nous éclairer sur la fonction spécialisée de la caspase-7, mais d’autres réplicas devront être faits.Abstract: Caspases are a family of cysteine proteases involved in several types of programmed cell death, such as apoptosis, an essential cell death process used to maintain homeostasis of the body consisting in the replacement of a defective cell by a new one in just a few hours. Caspase-3 and -7 are the proteases mainly responsible for the execution of apoptosis; caspase-3 is thought to be the key caspase because of its higher intrinsic activity. However, caspase-7 seems to have a more specialized role since it can cleave certain substrates faster because of an exosite. An exosite is an additional binding domain located outside the catalytic pocket of an enzyme. The caspase-7 exosite is primarily composed of four lysine residues (K38KKK) and forms a positively charged region that allows it to bind PARP-1 and p23 to increase their cleavage efficacy. We propose that the exosite of caspase-7 can bind different structures or proteins in the cell. Our goal was to identify among the substrates of caspase-7 those that interact with the exosite. To do so, we have tested and optimized five methods using mass spectrometry. Of the five, two methods allowed us to identify proteins potentially cleaved by caspase-7. The first method consisted of in vitro cleavage of metabolically-labeled cell extracts (SILAC) followed by a shotgun mass spectrometry analysis. With this method, we established a list of proteins potentially interacting with the caspase-7 exosite. Then, the most promising targets based on SILAC quantification and on protein function have been validated. We have confirmed that Thymidylate synthase (TYMS) is cleaved by caspase-3 but does not seem to be a caspase-7 substrate. Also, Fibroblast growth factor receptor (FGFR1) was another potential substrate of caspases, but it could not be confirmed with certainty. Since protein validation did not permit the identification of new caspase-7 substrates, another method was developed that consisted of in cellulo cleavage in apoptotic cells followed by enrichment of cleavage peptides by the TAILS method and a mass spectrometry analysis. This method allowed us to identify ten proteins that are potentially cleaved more rapidly by caspase-7 than by caspase-3. Also, based on evidence from the literature, we tried to confirm if some isoforms of Protein kinase C (PKC) cleaved by caspase-7 could interact with its exosite, but did not succeed. Our hypothesis remains unvalidated, but the cellular function of these substrates could enlighten us on the specialized role of caspase-7, but further replicas of this method are needed

Guidelines for the reliable use of high throughput sequencing technologies to detect plant pathogens and pests

High-throughput sequencing (HTS) technologies have the potential to become one of the most significant advances in molecular diagnostics. Their use by researchers to detect and characterize plant pathogens and pests has been growing steadily for more than a decade and they are now envisioned as a routine diagnostic test to be deployed by plant pest diagnostics laboratories. Nevertheless, HTS technologies and downstream bioinformatics analysis of the generated datasets represent a complex process including many steps whose reliability must be ensured. The aim of the present guidelines is to provide recommendations for researchers and diagnosticians aiming to reliably use HTS technologies to detect plant pathogens and pests. These guidelines are generic and do not depend on the sequencing technology or platform. They cover all the adoption processes of HTS technologies from test selection to test validation as well as their routine implementation. A special emphasis is given to key elements to be considered: undertaking a risk analysis, designing sample panels for validation, using proper controls, evaluating performance criteria, confirming and interpreting results. These guidelines cover any HTS test used for the detection and identification of any plant pest (viroid, virus, bacteria, phytoplasma, fungi and fungus-like protists, nematodes, arthropods, plants) from any type of matrix. Overall, their adoption by diagnosticians and researchers should greatly improve the reliability of pathogens and pest diagnostics and foster the use of HTS technologies in plant health