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Simple Summary: This study examines how altitude affects the fatty acid composition of pasture grass, yak milk, and yak ghee on the Qinghai–Tibet Plateau. It aims to understand how environmental factors, particularly altitude, influence the nutritional quality of these products. The results indicate that higher altitudes correlate with a greater presence of beneficial unsaturated fatty acids, such as oleic acid (C18:1) and linoleic acid (C18:2n6c), suggesting that yaks adapt to their high-altitude surroundings. These adaptations positively impact the quality of yak milk and yak ghee, essential food sources for local communities. By emphasizing the connection between altitude and fatty acid profiles, this research offers insights that can enhance dairy production practices. Ultimately, it aims to improve nutrition and food security for residents in high-altitude regions, ensuring access to nutritious food options. This study investigates the effect of altitude on the fatty acid composition of pasture grass, yak milk, and yak ghee on the Qinghai–Tibet Plateau, aiming to understand how environmental factors influence the nutritional quality of these products. Samples were collected from four different altitudes and analyzed for fatty acid profiles using gas chromatography. The analysis reveals that higher altitudes are associated with an increased prevalence of beneficial unsaturated fatty acids, such as oleic acid (C18:1) and linoleic acid (C18:2n6c). These findings highlight the significant influence of altitude on yak lipid metabolism, ultimately enhancing the nutritional value of dairy products. This adaptation not only supports the health and resilience of yaks, but also provides vital nutritional benefits to residents in high-altitude regions. The research underscores the importance of further investigations to optimize dairy production practices, ensuring improved food security and health outcomes for residents of the plateau. [ABSTRACT FROM AUTHOR]

Introduction Amomi Fructus (Sha ren) is an important traditional Chinese medicine that displays diverse medicinal functions such as dissipating dampness, warming the spleen, and preventing miscarriage, among other properties embodied [...], Amomum villosum Lour. is an important Chinese medicinal plant that has diverse medicinal functions, and mainly contains volatile terpenes. This study aims to explore the WRKY transcription factors (TFs) and terpene synthase (TPS) unigenes that might be involved in terpene biosynthesis in A. villosum, and thus providing some new information on the regulation of terpenes in plants. RNA sequencing of A. villosum induced by methyl jasmonate (MeJA) revealed that the WRKY family was the second largest TF family in the transcriptome. Thirty-six complete WRKY domain sequences were expressed in response to MeJA. Further, six WRKY unigenes were highly correlated with eight deduced TPS unigenes. Ultimately, we combined the terpene abundance with the expression of candidate WRKY TFs and TPS unigenes to presume a possible model wherein AvWRKY61, AvWRKY28, and AvWRKY40 might coordinately trans-activate the AvNeoD promoter. We propose an approach to further investigate TF unigenes that might be involved in terpenoid biosynthesis, and identified four unigenes for further analyses. Key words: RNA sequencing, WRKY transcription factors, terpene synthases, Amomum villosum Lour. L'Amomum villosum Lour. est une plante medicinale chinoise qui a plusieurs usages medicinaux et contient principalement des terpenes volatils. Cette etude visait a explorer les genes codant pour des facteurs de transcription (TF) WRKY ainsi que pour les terpenes synthases (TPS), lesquels sont potentiellement impliques dans la synthese des terpenes chez l'A. villosum,envue d'apporter un eclairage nouveau sur la regulation des terpenes chez les plantes. Le sequencage des ARN exprimes lorsque l'A. villosum est traite au methyljasmonate (MeJA) a revele que la famille des WRKY etait la seconde plus grande famille de TF au sein du transcriptome. Trente-six sequences presentant un domaine WRKY complet etaient exprimes en reponse au MeJA. De plus, six unigenes WRKY etaient fortement correles avec huit unigenes de TPS predits. Ultimement, les auteurs ont combine les donnees sur l abondance des terpenes et celles sur l'expression des WRKY et genes TPS candidats pour elaborer un modele possible ou AvWRKY61, AvWRKY28 et AvWRKY40 coordonneraient ensemble la trans-activation du promoteur AvNeoD. Les auteurs proposent une approche pour etudier plus en profondeur les genes codant pour des TF qui sont possiblement impliques dans la synthese des terpenoides et ils ont identifie quatre genes candidats meritant des analyses ulterieures. [Traduit par la Redaction] Mots-cles : sequencage de l'ARN, facteurs de transcription WRKY, terpenes synthases, Amomum villosum Lour.

Amomum villosum, also known as Fructus Amomi, has been used to treat digestive diseases such as abdominal pain, vomiting, and dysentery. Volatile terpenoids are the active metabolites in the essential oil of Fructus Amomi. Nevertheless, downstream genes responsible for activating metabolites biosynthesis in A. villosum still remain unclear. Here, we report the use of an integrative volatile terpenoid profiling and transcriptomics analysis for mining the corresponding genes involved in volatile terpenoid biosynthesis. Ten terpene synthase (TPS) genes were discovered, and two of them were cloned and functionally characterized. AvTPS1 (AvPS: pinene synthase) catalyzed GPP to form α-pinene and β-pinene; AvTPS3 (AvBPPS: bornyl diphosphate synthase) produced bornyl diphosphate as major product and the other three monoterpenoids as minor products. Metabolite accumulation and gene expression pattern combined with AvPS biochemical characterization suggested that AvPS might play a role in biotic defense. On the other hand, the most active ingredient, bornyl acetate, was highly accumulated in seeds and was consistent with the high expression of AvBPPS, which further indicated that AvBPPS is responsible for the biosynthesis of bornyl acetate, the final metabolite of bornyl diphosphate in A. villosum. This study can be used to improve the quality of A. villosum through metabolic engineering, and for the sustainable production of bornyl acetate in heterologous hosts. [ABSTRACT FROM AUTHOR]

Artemisia annua is the only medicinal crop that produces artemisinin for malarial treatment. Herein, we describe the cloning of a cinnamyl alcohol dehydrogenase (AaCAD) from an inbred self-pollinating (SP) A. annua cultivar and its effects on lignin and artemisinin production. A recombinant AaCAD was purified via heterogeneous expression. Enzyme assays showed that the recombinant AaCAD converted p-coumaryl, coniferyl, and sinapyl aldehydes to their corresponding alcohols, which are key intermediates involved in the biosynthesis of lignin. Km, Vmax, and Vmax/Km values were calculated for all three substrates. To characterize its function in planta, AaCAD was overexpressed in SP plants. Quantification using acetyl bromide (AcBr) showed significantly higher lignin contents in transgenics compared with wild-type (WT) plants. Moreover, GC-MS-based profiling revealed a significant increase in coumarin contents in transgenic plants. By contrast, HPLC-MS analysis showed significantly reduced artemisinin contents in transgenics compared with WT plants. Furthermore, GC-MS analysis revealed a decrease in the contents of arteannuin B and six other sesquiterpenes in transgenic plants. Confocal microscopy analysis showed the cytosolic localization of AaCAD. These data demonstrate that AaCAD plays a dual pathway function in the cytosol, in which it positively enhances lignin formation but negatively controls artemisinin formation. Based on these data, crosstalk between these two pathways mediated by AaCAD catalysis is discussed to understand the metabolic control of artemisinin biosynthesis in plants for high production. [ABSTRACT FROM AUTHOR]