Overexpression of the MYB29 transcription factor affects aliphatic glucosinolate synthesis in Brassica oleracea

Isothiocyanates, the bio-active hydrolysis products of glucosinolates, naturally produced by several Brassicaceae species, play an important role in human health and agriculture. This study aims at correlating the content of aliphatic glucosinolates to the expression of genes involved in their synthesis in Brassica oleracea, and perform functional analysis of BoMYB29 gene. To this purpose, three genotypes were used: a sprouting broccoli, a cabbage, and a wild genotype (Winspit), a high glucosinolate containing accession. Winspit showed the highest transcript level of BoMYB28, BoMYB29 and BoAOP2 genes, and BoAOP2 expression was positively correlated with that of the two MYB genes. Further analyses of the aliphatic glucosinolates also showed a positive correlation between the expression of BoAOP2 and the production of sinigrin and gluconapin in Winspit. The Winspit BoMYB29 CDS was cloned and overexpressed in Winspit and in the DH AG1012 line. Overexpressing Winspit plants produced higher quantities of alkenyl glucosinolates, such as sinigrin. Conversely, the DH AG1012 transformants showed a higher production of methylsulphinylalkyl glucosinolates, including glucoraphanin, and, despite an up-regulation of the aliphatic glucosinolate genes, no increase in alkenyl glucosinolates. The latter may be explained by the absence of a functional AOP2 gene in DH AG1012. Nevertheless, an extract of DH AG1012 lines overexpressing BoMYB29 provided a chemoprotective effect on human colon cells. This work exemplifies how the genetic diversity of B. oleracea may be used by breeders to select for higher expression of transcription factors for glucosinolate biosynthesis to improve its natural, health-promoting properties

Boekbespreking

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Quantitative Social Dialectology: Explaining Linguistic Variation Geographically and Socially

In this study we examine linguistic variation and its dependence on both social and geographic factors. We follow dialectometry in applying a quantitative methodology and focusing on dialect distances, and social dialectology in the choice of factors we examine in building a model to predict word pronunciation distances from the standard Dutch language to 424 Dutch dialects. We combine linear mixed-effects regression modeling with generalized additive modeling to predict the pronunciation distance of 559 words. Although geographical position is the dominant predictor, several other factors emerged as significant. The model predicts a greater distance from the standard for smaller communities, for communities with a higher average age, for nouns (as contrasted with verbs and adjectives), for more frequent words, and for words with relatively many vowels. The impact of the demographic variables, however, varied from word to word. For a majority of words, larger, richer and younger communities are moving towards the standard. For a smaller minority of words, larger, richer and younger communities emerge as driving a change away from the standard. Similarly, the strength of the effects of word frequency and word category varied geographically. The peripheral areas of the Netherlands showed a greater distance from the standard for nouns (as opposed to verbs and adjectives) as well as for high-frequency words, compared to the more central areas. Our findings indicate that changes in pronunciation have been spreading (in particular for low-frequency words) from the Hollandic center of economic power to the peripheral areas of the country, meeting resistance that is stronger wherever, for well-documented historical reasons, the political influence of Holland was reduced. Our results are also consistent with the theory of lexical diffusion, in that distances from the Hollandic norm vary systematically and predictably on a word by word basis

[Kaart van dialectvormen voor] de kikvors

Taal- en dialectkundigen van de Koninklijke Nederlandse Academie van Wetenschappen (KNAW) en van de Rijksuniversiteit Leiden en de Katholieke Universiteit van Leuven zijn vanaf 1939 bezig geweest aan de productie van een taal- en dialectatlas van het Nederlands. Deze atlas was in eerste instantie gebaseerd op een enquête onder een groot aantal respondenten – in totaal bijna 2.000, verdeeld over Nederland en Vlaanderen. Die respondenten werd gevraagd de plaatselijke vormen op te schrijven van een groot aantal begrippen. Door overeenkomstige antwoorden overeenkomstig te visualiseren (met hetzelfde symbool) en verwante woorden met op elkaar gelijkende symbolen aan te geven is voor elk van die begrippen de verspreiding van specifieke ‘vertalingen’ ervan in dialectvorm gekarteerd. Op basis van de verschillen of overeenkomsten tussen die verbreidingsvormen kon men uitspraken doen over de begrenzing van de verschillende dialecten van het Nederlands. Men zou dus kunnen zeggen dat deze taalatlas aan de kaart uit 1899 van Te Winkel (zie elders in deze collectie van gedigitaliseerde kaarten) eigenlijk vooraf had moeten gaan. De kaart is dus vooral bijzonder vanwege de manier waarop de gegevens middels een enquête onder respondenten verzameld zijn