The Overlooked Hybrid: Geographic Distribution and Niche Differentiation Between Spartina Cytotypes (Poaceae) in Wadden Sea Salt Marshes

Whole genome duplications (WGDs) lead to polyploid specimens and are regarded as major drivers for speciation and diversification in plants. One prevalent problem when studying WGDs is that effects of polyploidization in ancient polyploids cannot be disentangled from the consequences of selective evolutionary forces. Cytotypic differences in distribution, phenotypic appearance and in response to surface elevation (determined by HOF-modeling) were identified in a relatively young taxa-group of a hexaploid F₁-hybrid (Spartina× townsendii H. Groves & J. Groves, Poaceae) and its dodecaploid descendent (Spartina anglica C.E. Hubbard, Poaceae) using vegetation assessments (1029 plots; 1 × 1 m²) from the European Wadden Sea mainland salt marshes, including elevational and mean high tidal (MHT) data. While the F₁-hybrid was mainly present in the eastern part of the Wadden Sea, its dodecaploid descendent occurred in the entire Wadden Sea area. The Spartina cytotypes differed in phenotypes (median of Spartina cover: hexaploid = 25% vs. dodecaploid = 12%) and in elevational niche-optimum (hexaploid = − 49.5 cm MHT vs. dodecaploid = 8.0 cm MHT). High ploidy levels correlated with establishment success in Spartina along geographic gradients but did not seem to increase the capacity to cope with abiotic severity downwards the elevational gradient in salt marshes

B1‐type cyclins control microtubule organization during cell division in Arabidopsis

Flowering plants contain a large number of cyclin families, each containing multiple members, most of which have not been characterized to date. Here, we analyzed the role of the B1 subclass of mitotic cyclins in cell cycle control during Arabidopsis development. While we reveal CYCB1;5 to be a pseudogene, the remaining four members were found to be expressed in dividing cells. Mutant analyses showed a complex pattern of overlapping, development-specific requirements of B1-type cyclins with CYCB1;2 playing a central role. The double mutant cycb1;1 cycb1;2 is severely compromised in growth, yet viable beyond the seedling stage, hence representing a unique opportunity to study the function of B1-type cyclin activity at the organismic level. Immunolocalization of microtubules in cycb1;1 cycb1;2 and treating mutants with the microtubule drug oryzalin revealed a key role of B1-type cyclins in orchestrating mitotic microtubule networks. Subsequently, we identified the GAMMA-TUBULIN COMPLEX PROTEIN 3-INTERACTING PROTEIN 1 (GIP1/MOZART) as an in vitro substrate of B1-type cyclin complexes and further genetic analyses support a potential role in the regulation of GIP1 by CYCB1s

B1-type cyclins control microtubule organization during cell division in Arabidopsis

Flowering plants contain a large number of cyclin families, each containing multiple members, most of which have not been characterized to date. Here, we analyzed the role of the B1 subclass of mitotic cyclins in cell cycle control during Arabidopsis development. While we reveal CYCB1;5 to be a pseudogene, the remaining four members were found to be expressed in dividing cells. Mutant analyses showed a complex pattern of overlapping, development-specific requirements of B1-type cyclins with CYCB1;2 playing a central role. The double mutant cycb1;1 cycb1;2 is severely compromised in growth, yet viable beyond the seedling stage, hence representing a unique opportunity to study the function of B1-type cyclin activity at the organismic level. Immunolocalization of microtubules in cycb1;1 cycb1;2 and treating mutants with the microtubule drug oryzalin revealed a key role of B1-type cyclins in orchestrating mitotic microtubule networks. Subsequently, we identified the GAMMA-TUBULIN COMPLEX PROTEIN 3-INTERACING PROTEIN 1 (GIP1/MOZART) as an in vitro substrate of B1-type cyclin complexes and further genetic analyses support an important role in the regulation of GIP1 by CYCB1s

Recalled and recorded bowel habits confirm early onset and high frequency of constipation in day-care nursery children Relato e registro do hábito intestinal de crianças em creches confirmam alta frequência e início precoce de constipação

CONTEXT: Mothers recall early-onset constipation in children attending gastroenterology clinics. OBJECTIVES: To study the bowel habit of young children in the community to determine, first, whether early-onset constipation is confirmed in this setting and, second, the agreement between recalled and recorded bowel habit. METHODS:Defecation data of 57 children aged 6.0-40.7 mo were obtained by maternal recall (questionnaire on predominant stool characteristics) and by record (1,934 defecations registered prospectively at home and in the nursery). The bowel habit was classified according to stool frequency and proportion of stool characteristics (soft, hard and/or runny). Two criteria were used to classify recorded data, since the cutoff point for hard stools to identify constipation is undefined in children: predominant criterion and adult criterion, respectively with >50% and >25% of stools with altered consistency. Bowel habit categories were: adequate, constipation, functional diarrhea and "other bowel habit". Nonparametric statistics, and the Kappa index for agreement between recalled and recorded bowel habit, were used. RESULTS: Constipation occurred in 17.5%, 10.5%, 19.3% of the children by recall, the predominant and the adult criteria, respectively. Constipation was the main recalled alteration, vs 12.3% "other bowel habit". Only one child classified as having functional diarrhea (by the adult criterion). Agreement between recalled and recorded bowel habit was fair for constipation, by the predominant and the adult criteria (K = 0.28 and 0.24, respectively), but only slight (K <0.16) for other bowel habit categories. Individual data, however, pointed to a better relationship between recalled constipation and the adult rather than the predominant criterion. CONCLUSIONS: Frequent early-onset constipation was confirmed. Fair agreement between recalled and recorded constipation by the two used criteria indicates that recalled data are quite reliable to detect constipation.<br>CONTEXTO: Mães relatam início precoce de constipação em crianças atendidas em clínicas de gastroenterologia. OBJETIVOS: Estudar o hábito intestinal em crianças de baixa idade na comunidade, para avaliar se início precoce da constipação é confirmado neste contexto e se há concordância entre o hábito intestinal relatado e o registrado prospectivamente. MÉTODOS: Obtiveram-se dados sobre evacuações de 57 crianças com idade 6.0-40.7 meses, mediante relato materno (questionário sobre características fecais predominantes) e, a seguir, foram registradas 1.934 evacuações em casa e na creche. O hábito intestinal foi classificado como adequado, constipação, diarréia funcional, "outro hábito intestinal", conforme frequência evacuatória e proporção das características fecais (macias, duras e/ou que escorrem). Usaram-se dois critérios para classificar o hábito intestinal registrado, devido indefinição no ponto de corte para fezes duras na identificação de constipação em crianças: critério predominante e critério adulto, respectivamente com >50% e >25% de evacuações com consistência alterada. Usou-se estatística não-paramétrica e, para concordância entre hábito intestinal relatado e registrado, o índice Kappa. RESULTADOS: Constipação ocorreu em 17.5%, 10.5%, 19.3% das crianças, respectivamente pelo relato e pelo registro segundo critérios predominante e adulto. Constipação foi o hábito intestinal mais frequentemente relatado, versus 12.3% "outro hábito intestinal". Só uma criança se classificou como tendo diarréia funcional (pelo critério adulto). Concordância entre o hábito intestinal relatado e o registrado foi razoável ("fair") para constipação, pelos critérios predominante e adulto (K=0.28 e 0.24, respectivamente), mas apenas leve ("slight") para os demais hábito intestinal (K <0.16). Entretanto, dados individuais indicaram melhor relação entre relato de constipação com o critério adulto do que com o critério predominante. CONCLUSÕES: Confirmou-se que constipação é frequente e de início precoce. Concordância razoável entre o hábito intestinal relatado e o registrado segundo os dois critérios indica que o relato materno é razoavelmente confiável para detectar constipação