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Boron (B) is essential for plant growth, but toxic in excess. In several countries, soil toxic B levels are always a severe agricultural problem in arid and semi-arid regions. Phytoremediation of excess B containing soil is still in its infancy, while high B tolerant plants with elevated protein abundance of B efflux transporter were successfully established or explored. Brassica napus (B. napus) is one of the most important oil crops. However, B efflux transporters underlying excess B tolerance in B. napus remain unknown. Here, we reported that in Brassicaceae species, B. napus had four homologous genes of Arabidopsis AtBOR4 , which were renamed BnaBOR4.1, BnaBOR4.2, BnaBOR4.3 and BnaBOR4.4. BnaBOR4.1, BnaBOR4.2 and BnaBOR4.3 showed constitutive expression and BnaBOR4.4 appeared to be a pseudogene. BnaBOR4.2 and BnaBOR4.3 were expressed in inner cell layers and BnaBOR4.1 in the outer cell layer in root tip, and all were expressed in vascular tissue in the mature zone. B efflux activity assays in yeast demonstrated that BnaBOR4.1, BnaBOR4.2 and AtBOR4 but not BnaBOR4.3 had comparable levels of B transport activity. Structure-functional analysis between BnaBOR4.3 and BnaBOR4.2 demonstrated that amino acid residue substitution at position 297 (Ala vs Pro) and 427 (Met vs Leu) is critical for the B transport activity. Mutant BnaBOR4.3 M427L partially restored the B efflux activity, and both mutants BnaBOR4.3 A297P and BnaBOR4.3 A297P&M427L fully restored B efflux activity, indicating that the Pro297 residue is critical for their function. Further validation of BnaBOR4 was accomplished by growing transgenic Arabidopsis plants under high B conditions. Taken together, our study identified two functional B efflux genes BnaBOR4.1 and BnaBOR4.2 in B. napus, and a key amino acid residue proline 297 associated with B efflux activity. This study highlights the potential of BanBOR4 genes for B. napus cultivation under high B stress., Competing Interests: Declaration of Competing Interest I declare on behalf of my co-authors that the work described is an original research that has not been published previously, and the manuscript has not been under consideration for publication elsewhere, in whole or in part. No conflict of interest exits in the submission of this manuscript, and the manuscript has been approved by all the authors for publication., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Peeling of citrus fruits is the key procedure in the production of citrus products such as canned citrus and citrus vinegar. In order to facilitate this peeling process, Citrus reticulata Blanco is usually heated. The treatments of steam blanching and air cooling were carried out in the citrus peeling experiment. The anatomical details of citrus peel were also observed after steam blanching. The results indicated that the duration of steam blanching had a significant influence on peelability of Citrus reticulata Blanco ( P  < 0.01). With the proceeding of steam blanching, the maximum stripping force and the maximum stripping length of the citrus peel decreased. Two minutes after steam blanching, parenchyma cell structure and vascular elements were destroyed. The duration of cooling treatment has no significant impact on the peelability of the citrus ( P  > 0.05). The content of titratable acid, total soluble solid and vitamin C were considerably influenced by steam blanching. When steam blanching duration was within 2 min, the color change ∆E ij was less than 3.0, indicating no significant color change. This study determined 2 min to be the optimal steam blanching duration for achieving the best peelability and quality of peeled citrus, and 5 min or less to be optimal cooling duration. Overall, this study provides a theoretical guideline for the application of the steam blanching treatment in the citrus production., (© Association of Food Scientists & Technologists (India) 2020.)

Laron syndrome, also known as growth hormone insensitivity syndrome (GHIS), is an autosomal recessive genetic disorder associated with severe postnatal growth failure, and normal and/or elevated growth hormone. This disease is frequently caused by a point mutation in the growth hormone receptor gene (GHR). Here, we identified a novel homozygous substitution mutation (E42K: GAG-->AAG at codon 42 cDNA) of the GHR gene in a Chinese girl with Laron syndrome. This mutation was predicted to impair the GHR binding affinity to human growth hormone (hGH), and was responsible for low levels of insulin-like growth factor (IGF)-I, IGF binding protein (IGFBP)-3, and GH binding protein (GHBP) in serum.