Recent advances in molecular technology have revolutionized research on all aspects of the biology of organisms, including ciliates, and created unprecedented opportunities for pursuing a more integrative approach to investigations of biodiversity. However, this goal is complicated by large gaps and inconsistencies that still exist in the foundation of basic information about biodiversity of ciliates. The present paper reviews issues relating to the taxonomy of ciliates and presents specific recommendations for best practice in the observation and documentation of their biodiversity. This effort stems from a workshop that explored ways to implement six Grand Challenges proposed by the International Research Coordination Network for Biodiversity of Ciliates (IRCN-BC). As part of its commitment to strengthening the knowledge base that supports research on biodiversity of ciliates, the IRCN-BC proposes to populate The Ciliate Guide, an online database, with biodiversity-related data and metadata to create a resource that will facilitate accurate taxonomic identifications and promote sharing of data.

• MeSH
• biodiverzita MeSH
• Ciliophora klasifikace   genetika   MeSH
• databáze faktografické * MeSH
• fylogeneze MeSH
• internet MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Identification of mutants with impairments in auxin biosynthesis and dynamics by forward genetic screening is hindered by the complexity, redundancy and necessity of the pathways involved. Furthermore, although a few auxin-deficient mutants have been recently identified by screening for altered responses to shade, ethylene, N-1-naphthylphthalamic acid (NPA) or cytokinin (CK), there is still a lack of robust markers for systematically isolating such mutants. We hypothesized that a potentially suitable phenotypic marker is root curling induced by CK, as observed in the auxin biosynthesis mutant CK-induced root curling 1 / tryptophan aminotransferase of Arabidopsis 1 (ckrc1/taa1). Phenotypic observations, genetic analyses and biochemical complementation tests of Arabidopsis seedlings displaying the trait in large-scale genetic screens showed that it can facilitate isolation of mutants with perturbations in auxin biosynthesis, transport and signaling. However, unlike transport/signaling mutants, the curled (or wavy) root phenotypes of auxin-deficient mutants were significantly induced by CKs and could be rescued by exogenous auxins. Mutants allelic to several known auxin biosynthesis mutants were re-isolated, but several new classes of auxin-deficient mutants were also isolated. The findings show that CK-induced root curling provides an effective marker for discovering genes involved in auxin biosynthesis or homeostasis.

• MeSH
• Arabidopsis enzymologie   genetika   MeSH
• biologický transport účinky léků   MeSH
• cytokininy metabolismus   MeSH
• fenotyp MeSH
• kořeny rostlin enzymologie   genetika   růst a vývoj   MeSH
• kyseliny indoloctové metabolismus   farmakologie   MeSH
• mutace MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• regulátory růstu rostlin biosyntéza   MeSH
• semenáček účinky léků   růst a vývoj   metabolismus   MeSH
• signální transdukce účinky léků   MeSH
• tryptofantransaminasa genetika   metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Cytokinins (CKs) regulate plant development and growth via a two-component signaling pathway. By forward genetic screening, we isolated an Arabidopsis mutant named grow fast on cytokinins 1 (gfc1), whose seedlings grew larger aerial parts on MS medium with CK. gfc1 is allelic to a previously reported cutin mutant defective in cuticular ridges (dcr). GFC1/DCR encodes a soluble BAHD acyltransferase (a name based on the first four enzymes characterized in this family: Benzylalcohol O-acetyltransferase, Anthocyanin O-hydroxycinnamoyltransferase, anthranilate N-hydroxycinnamoyl/benzoyltransferase and Deacetylvindoline 4-O-acetyltransferase) with diacylglycerol acyltransferase (DGAT) activity in vitro and is necessary for normal cuticle formation on epidermis in vivo. Here we show that gfc1 was a CK-insensitive mutant, as revealed by its low regeneration frequency in vitro and resistance to CK in adventitious root formation and dark-grown hypocotyl inhibition assays. In addition, gfc1 had de-etiolated phenotypes in darkness and was therefore defective in skotomorphogenesis. The background expression levels of most type-A Arabidopsis Response Regulator (ARR) genes were higher in the gfc1 mutant. The gfc1-associated phenotypes were also observed in the cutin-deficient glycerol-3-phosphate acyltransferase 4/8 (gpat4/8) double mutant [defective in glycerol-3-phosphate (G3P) acyltransferase enzymes GPAT4 and GPAT8, which redundantly catalyze the acylation of G3P by hydroxyl fatty acid (OH-FA)], but not in the cutin-deficient mutant cytochrome p450, family 86, subfamily A, polypeptide 2/aberrant induction of type three 1 (cyp86A2/att1), which affects the biosynthesis of some OH-FAs. Our results indicate that some acyltransferases associated with cutin formation are involved in CK responses and skotomorphogenesis in Arabidopsis.

• MeSH
• acyltransferasy genetika   metabolismus   MeSH
• Arabidopsis genetika   růst a vývoj   metabolismus   účinky záření   MeSH
• cytokininy metabolismus   farmakologie   MeSH
• fenotyp MeSH
• membránové lipidy biosyntéza   MeSH
• meristém účinky léků   genetika   růst a vývoj   účinky záření   MeSH
• morfogeneze * účinky léků   účinky záření   MeSH
• mutace MeSH
• proteiny huseníčku genetika   metabolismus   MeSH
• regulace genové exprese u rostlin účinky léků   účinky záření   MeSH
• semenáček účinky léků   genetika   růst a vývoj   účinky záření   MeSH
• tma MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH