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Yang Z, Ren J, Lu S, Feng Y, Fan Y, Liu TX, Jing X. In vivo functional analysis of the cotton bollworm Helicoverpa armigera 24-dehydrocholesterol reductase (HaDHCR24) in phytosterol metabolism. INSECT SCIENCE 2024. [PMID: 38973264 DOI: 10.1111/1744-7917.13405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Revised: 05/03/2024] [Accepted: 05/10/2024] [Indexed: 07/09/2024]
Abstract
Insects have to obtain sterols from food due to the inability to synthesize this essential nutrient de novo. For lepidopteran insects, they can convert a variety of phytosterols into cholesterol to meet their growth needs. The final step of the cholesterol biosynthesis is the metabolism of desmosterol catalyzed by 24-dehydrocholesterol reductase (DHCR24). In this study, we identified a DHCR24 homolog in the cotton bollworm Helicoverpa armigera, designated as H. armigera 24-dehydrocholesterol reductase (HaDHCR24)-1. The quantitative expression analyses indicated that HaDHCR24-1 was highly enriched in the midgut where dietary sterol uptake occurs. Compared to the control, the DHCR24-1 mutant larvae generated by clustered regularly interspaced palindromic repeats (CRISPR) / CRISPR-associated nuclease 9 technology accumulated more desmosterol in the gut, while the content of cholesterol was significantly reduced. A similar phenomenon was observed when the DHCR24 inhibitor, amiodarone, was applied to the insects. Moreover, DHCR24-1 played an important role for the usage of β-sitosterol, a major sterol in plants, in H. armigera, and loss of function of DHCR24-1 resulted in higher mortality on β-sitosterol. However, the DHCR24 homolog does not necessarily exist in the genomes of all insects. The loss of this gene occurred more frequently in the insects feeding on animals, which further support the role of DHCR24-1 in using phytosterols. This gene may have important potential in developing new strategies to control herbivory pests in Lepidoptera and other insect orders.
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Affiliation(s)
- Zhen Yang
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Jinchan Ren
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Shuning Lu
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Yuanze Feng
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Yongliang Fan
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Tong-Xian Liu
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
| | - Xiangfeng Jing
- Key Laboratory of Plant Protection Resources and Pest Management of Ministry of Education, Key Laboratory of Integrated Pest Management on Crops in Northwestern Loess Plateau of Ministry of Agriculture and Rural Affairs, College of Plant Protection, Northwest A&F University, Yangling, Shaanxi, China
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Carlberg C, Raczyk M, Zawrotna N. Vitamin D: A master example of nutrigenomics. Redox Biol 2023; 62:102695. [PMID: 37043983 PMCID: PMC10119805 DOI: 10.1016/j.redox.2023.102695] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Accepted: 04/03/2023] [Indexed: 04/08/2023] Open
Abstract
Nutrigenomics attempts to characterize and integrate the relation between dietary molecules and gene expression on a genome-wide level. One of the biologically active nutritional compounds is vitamin D3, which activates via its metabolite 1α,25-dihydroxyvitamin D3 (1,25(OH)2D3) the nuclear receptor VDR (vitamin D receptor). Vitamin D3 can be synthesized endogenously in our skin, but since we spend long times indoors and often live at higher latitudes where for many winter months UV-B radiation is too low, it became a true vitamin. The ligand-inducible transcription factor VDR is expressed in the majority of human tissues and cell types, where it modulates the epigenome at thousands of genomic sites. In a tissue-specific fashion this results in the up- and downregulation of primary vitamin D target genes, some of which are involved in attenuating oxidative stress. Vitamin D affects a wide range of physiological functions including the control of metabolism, bone formation and immunity. In this review, we will discuss how the epigenome- and transcriptome-wide effects of 1,25(OH)2D3 and its receptor VDR serve as a master example in nutrigenomics. In this context, we will outline the basis of a mechanistic understanding for personalized nutrition with vitamin D3.
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The Non Catalytic Protein ERG28 has a Functional Role in Cholesterol Synthesis and is Coregulated Transcriptionally. J Lipid Res 2022; 63:100295. [PMID: 36216146 PMCID: PMC9730225 DOI: 10.1016/j.jlr.2022.100295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2021] [Revised: 08/30/2022] [Accepted: 10/03/2022] [Indexed: 11/06/2022] Open
Abstract
The enzymatic pathway of cholesterol biosynthesis has been well characterized. However, there remain several potential interacting proteins that may play ancillary roles in the regulation of cholesterol production. Here, we identified ERG28 (chromosome 14 open reading frame 1 [C14orf1]), a homologue of the yeast protein Erg28p, as a player in mammalian cholesterol synthesis. ERG28 is conserved from yeast to humans but has been largely overlooked in mammals. Using quantitative RT-PCR, luciferase assays, and publicly available chromatin immunoprecipitation sequencing data, we found that transcription of this gene is driven by the transcription factor SREBP-2, akin to most cholesterol synthesis enzymes, as well as identifying sterol-responsive elements and cofactor binding sites in its proximal promoter. Based on a split luciferase system, ERG28 interacted with itself and two enzymes of cholesterol synthesis (NSDHL and SC4MOL). Huh7 ERG28-KO cell lines were generated, revealing reduced total cholesterol levels in sterol-depleted environments. In addition, radiolabeled metabolic flux assays showed a 60-75% reduction in the rate of cholesterol synthesis in the KO versus wild-type cells, which could be rescued by expression of ectopic ERG28. Unexpectedly, KO of ERG28 also impaired the activation of SREBP-2 under sterol-replete conditions, by a yet-to-be defined mechanism. These results indicate that ERG28 is clearly involved in cholesterol synthesis, although the precise role this noncatalytic protein plays in this complex metabolic pathway remains to be fully elucidated. A deeper understanding of ERG28, and other ancillary proteins of cholesterol synthesis, may help inform therapeutic strategies for diseases associated with aberrant cholesterol metabolism.
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Vitamin D in the Context of Evolution. Nutrients 2022; 14:nu14153018. [PMID: 35893872 PMCID: PMC9332464 DOI: 10.3390/nu14153018] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 07/18/2022] [Accepted: 07/21/2022] [Indexed: 12/12/2022] Open
Abstract
For at least 1.2 billion years, eukaryotes have been able to synthesize sterols and, therefore, can produce vitamin D when exposed to UV-B. Vitamin D endocrinology was established some 550 million years ago in animals, when the high-affinity nuclear receptor VDR (vitamin D receptor), transport proteins and enzymes for vitamin D metabolism evolved. This enabled vitamin D to regulate, via its target genes, physiological process, the first of which were detoxification and energy metabolism. In this way, vitamin D was enabled to modulate the energy-consuming processes of the innate immune system in its fight against microbes. In the evolving adaptive immune system, vitamin D started to act as a negative regulator of growth, which prevents overboarding reactions of T cells in the context of autoimmune diseases. When, some 400 million years ago, species left the ocean and were exposed to gravitation, vitamin D endocrinology took over the additional role as a major regulator of calcium homeostasis, being important for a stable skeleton. Homo sapiens evolved approximately 300,000 years ago in East Africa and had adapted vitamin D endocrinology to the intensive exposure of the equatorial sun. However, when some 75,000 years ago, when anatomically modern humans started to populate all continents, they also reached regions with seasonally low or no UV-B, i.e., and under these conditions vitamin D became a vitamin.
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Trabelcy B, Gerchman Y, Sapir A. A sterol-defined system for quantitative studies of sterol metabolism in C. elegans. STAR Protoc 2021; 2:100710. [PMID: 34409305 PMCID: PMC8361321 DOI: 10.1016/j.xpro.2021.100710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
This protocol describes the culturing of the nematode Caenorhabditis elegans (C. elegans) in a sterol-defined experimental system and the subsequent quantitative analysis of C. elegans sterols through gas chromatography-mass spectrometry. Although studied primarily in mammals, sterols are essential biomolecules for most eukaryotes. C. elegans cannot synthesize sterols and thus relies on the uptake of dietary sterols. Therefore, C. elegans is a powerful system to study metabolism in sterol-defined conditions that are described in our protocol. For complete details on the use and execution of this protocol, please refer to Shamsuzzama et al. (2020).
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Affiliation(s)
- Benjamin Trabelcy
- Faculty of Natural Sciences, University of Haifa, Haifa 3498838 Israel
- Corresponding author
| | - Yoram Gerchman
- Faculty of Natural Sciences, University of Haifa, Haifa 3498838 Israel
| | - Amir Sapir
- Faculty of Natural Sciences, University of Haifa, Haifa 3498838 Israel
- Corresponding author
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Abstract
Extreme environments constitute the largest habitat on earth, but our understanding of life in such environments is rudimentary. The hostility of extreme environments such as the deep sea, earth’s crust, and toxic lakes limits the sampling, culturing, and studying of extremophiles, the organisms that live in these habitats. Thus, in terms of ecological research, extreme environments are the earth’s final frontier. A growing body of data suggests that nematodes are the most common animal taxon in different types of extreme settings such as the deep-subsurface and sediments in the deep sea. Notably, the reasons for the abundance of nematodes in extreme habitats remain mostly unknown. I propose that a unique combination of several characteristics of nematodes may explain, additively or synergistically, their successful adaptation to extreme habitats. Novel functional genetic and genomic approaches are expected to reveal molecular mechanisms of adaptation of nematodes to the many fascinating extreme environments on earth.
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Affiliation(s)
- Amir Sapir
- Faculty of Natural Sciences, University of Haifa, Haifa, Israel
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