A natural mutation in the promoter of Ms-cd1 causes dominant male sterility in Brassica oleracea.

Male sterility has been used for crop hybrid breeding for a long time. It has contributed greatly to crop yield increase. However, the genetic basis of male sterility has not been fully elucidated. Here, we report map-based cloning of the cabbage (Brassica oleracea) dominant male-sterile gene Ms-cd1 and reveal that it encodes a PHD-finger motif transcription factor. A natural allele Ms-cd1PΔ-597, resulting from a 1-bp deletion in the promoter, confers dominant genic male sterility (DGMS), whereas loss-of-function ms-cd1 mutant shows recessive male sterility. We also show that the ethylene response factor BoERF1L represses the expression of Ms-cd1 by directly binding to its promoter; however, the 1-bp deletion in Ms-cd1PΔ-597 affects the binding. Furthermore, ectopic expression of Ms-cd1PΔ-597 confers DGMS in both dicotyledonous and monocotyledonous plant species. We thus propose that the DGMS system could be useful for breeding hybrids of multiple crop species.

Map-based cloning and CRISPR/Cas9-based editing uncover BoNA1 as the causal gene for the no-anthocyanin-accumulation phenotype in curly kale (Brassica oleracea var. sabellica).

Brassica oleracea comprises several important vegetable and ornamental crops, including curly kale, ornamental kale, cabbage, broccoli, and others. The accumulation of anthocyanins, important secondary metabolites valuable to human health, in these plants varies widely and is responsible for their pink to dark purple colors. Some curly kale varieties lack anthocyanins, making these plants completely green. The genetic basis of this trait is still unknown. We crossed the curly kale inbred line BK2019 (without anthocyanins) with the cabbage inbred line YL1 (with anthocyanins) and the Chinese kale inbred line TO1000 (with anthocyanins) to generate segregating populations. The no-anthocyanin trait was genetically controlled by a recessive gene, bona1. We generated a linkage map and mapped bona1 to a 256-kb interval on C09. We identified one candidate gene, Bo9g058630, in the target genomic region; this gene is homologous to AT5G42800, which encodes a dihydroflavonol-4-reductase-like (DFR-like) protein in Arabidopsis. In BK2019, a 1-bp insertion was observed in the second exon of Bo9g058630 and directly produced a stop codon. To verify the candidate gene function, CRISPR/Cas9 gene editing technology was applied to knock out Bo9g058630. We generated three bona1 mutants, two of which were completely green with no anthocyanins, confirming that Bo9g058630 corresponds to BoNA1. Different insertion/deletion mutations in BoNA1 exons were found in all six of the other no-anthocyanin kale varieties examined, supporting that independent disruption of BoNA1 resulted in no-anthocyanin varieties of B. oleracea. This study improves the understanding of the regulation mechanism of anthocyanin accumulation in B. oleracea subspecies.

What learning strategies influence higher-order learning behaviours of medical students?

AIMS: The aim of this study was to explore the relationship between the application of learning strategies and the emergence of higher-order learning behaviours among medical students in Chinese provincial undergraduate colleges, while also examining the impact of social demographic variables on the development of higher-order learning behaviours and learning strategy preferences. METHODOLOGY: We conducted a relevant cross-sectional study using the Chinese College Student Survey (CCSS) online questionnaire to evaluate higher-order learning behaviours and learning strategies in medical undergraduate students attending provincial colleges in China. A total of 992 valid questionnaires were collected and analysed using SPSS 22.0 (SPSS Inc., Chicago, IL). We performed statistical analysis using one-sample t-tests to compare the results with the national norm score for medical subjects in undergraduate colleges. We also conducted variance analysis and regression analysis. RESULTS: The study found that the average scores for higher-order learning behaviours, enquiry-based learning and receptive learning behaviour among medical undergraduate students in provincial colleges were higher than the national norm score for medical subjects, indicating a positive trend. However, the average scores for other indicators were lower than the national norm score. The utilization of learning strategies and the development of higher-order learning behaviours among students were affected by various factors such as grade and gender. The study suggests that the preference for certain learning strategies, such as enquiry-based, receptive, integrative and collaborative, can have a significant impact on the emergence of higher-order learning behaviours. CONCLUSIONS: The study has demonstrated a positive correlation between the utilization of learning strategies and the development of higher-order learning behaviours. This relationship has been observed in medical students attending provincial undergraduate colleges, where the adoption of enquiry-based, receptive, integrative and collaborative learning strategies has been found to significantly influence the emergence of higher-order learning behaviours.KEY MESSAGESThe implementation of learning strategies among medical students in provincial undergraduate colleges in China has a significant impact on high-level learning behaviours.The impact of high-level learning behaviours is reliant on comprehensive support from four distinct learning strategies: receptive learning, inquiry-based learning, comprehensive learning and collaborative learning.One of the most impactful learning strategies is receptive learning, particularly on high-order learning behaviours. On the other hand, reflective learning does not seem to have a significant effect.Changes in grades can significantly impact higher-order learning behaviours and affect the propensity for reflective and collaborative learning strategies.Females generally exhibit a greater preference for receptive learning strategies, while males tend to exhibit a greater preference for inquiry-based learning strategies.

In Situ Synthesis of Bi2MoO6/Bi2SiO5 Heterojunction for Efficient Degrading of Persistent Pollutants.

Photocatalytic degradation is an environmentally friendly way to eliminate environmental pollution. Exploring a photocatalyst with high efficiency is essential. In the present study, we fabricated a Bi2MoO6/Bi2SiO5 heterojunction (BMOS) with intimate interfaces via a facile in situ synthesis method. The BMOS had much better photocatalytic performance than pure Bi2MoO6 and Bi2SiO5. The sample of BMOS-3 (3:1 molar ratio of Mo:Si) had the highest removal efficiency by the degradation of Rhodamine B (RhB) up to 75% and tetracycline (TC) up to 62% within 180 min. The increase in photocatalytic activity can be attributed to constructing high-energy electron orbitals in Bi2MoO6 to form a type II heterojunction, which increases the separation efficiencies of photogenerated carriers and transfer between the interface of Bi2MoO6 and Bi2SiO5. Moreover, electron spin resonance analysis and trapping experiments showed that the main active species were h+ and •O2- during photodegradation. BMOS-3 maintained a stable degradation capacity of 65% (RhB) and 49% (TC) after three stability experiments. This work offers a rational strategy to build Bi-based type II heterojunctions for the efficient photodegradation of persistent pollutants.

Fine mapping and candidate gene identification of the genic male-sterile gene ms3 in cabbage 51S.

KEY MESSAGE: The ms3 gene responsible for a male-sterile phenotype in cabbage was mapped to a 187.4-kb genomic fragment. The gene BoTPD1, a homolog of Arabidopsis TPD1, was identified as a strong candidate gene. Cabbage 51S is a spontaneous male-sterile mutant. Phenotypic investigation revealed defects in anther cell differentiation, with failure to form the tapetum layer and complete abortion of microsporocytes before the tetrad stage. Genetic analysis indicated that this male sterility was controlled by a single recessive gene, ms3. Using an F2 population, we mapped ms3 to a 187.4-kb interval. BoTPD1 was identified as a candidate from this interval. Sequence analysis revealed an intronic 182-bp insertion in 51S that interrupted the conserved motif at the 5' splicing site of the third intron, possibly resulting in a truncated transcript. Analyses of BoTPD1 homologous proteins revealed evolutionarily conserved roles in anther cell fate determination during reproductive development. RT-PCR showed that BoTPD1 was expressed in various tissues, excluding the root, and high expression levels were detected in anthers and buds. A BoTPD1-specific marker based on the 182-bp insertion cosegregated with male sterility and can be used for marker-assisted selection.