Novel Functions of the Fatty Acid and Retinol Binding Protein (FAR) Gene Family Revealed by Fungus-Mediated RNAi in the Parasitic Nematode, Aphelenchoides besseyi

RNA interference (RNAi) is a powerful tool for the analysis of gene function in nematodes. Fatty acid and retinol binding protein (FAR) is a protein that only exists in nematodes and plays an important role in their life activities. The rice white-tip nematode (RWTN), Aphelenchoides besseyi, is a migratory endoparasitic plant nematode that causes serious damage in agricultural production. In this study, the expression levels of eight RWTN genes were effectively decreased when RWTN was fed Ab-far-n (n: 1–8) hairpin RNA transgenic Botrytis cinerea (ARTBn). These functions of the far gene family were identified to be consistent and diverse through phenotypic changes after any gene was silenced. Such consistency indicates that the body lengths of the females were significantly shortened after silencing any of the eight Ab-far genes. The diversities were mainly manifested as follows: (1) Reproduction of nematodes was clearly inhibited after Ab-far-1 to Ab-far-4 were silenced. In addition, silencing Ab-far-2 could inhibit the pathogenicity of nematodes to Arabidopsis; (2) gonad length of female nematodes was significantly shortened after Ab-far-2 and Ab-far-4 were silenced; (3) proportion of male nematodes significantly increased in the adult population after Ab-far-1, Ab-far-3, and Ab-far-5 were silenced, whereas the proportion of adult nematodes significantly decreased in the nematode population after Ab-far-4 were silenced. (4) Fat storage of nematodes significantly decreased after Ab-far-3, Ab-far-4, and Ab-far-7 were silenced. To our knowledge, this is the first study to demonstrate that Ab-far genes affect sex formation and lipid metabolism in nematodes, which provides valuable data for further study and control of RWTNs.

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A new fungus-mediated RNAi method established and used to study the fatty acid and retinol binding protein function of the plant-parasitic nematode Aphelenchoides besseyi

RNA Biology ◽

10.1080/15476286.2020.1852779 ◽

2020 ◽

pp. 1-10

Author(s):

Shanwen Ding ◽

Dongwei Wang ◽

Chunling Xu ◽

Sihua Yang ◽

Xi Cheng ◽

...

Keyword(s):

Fatty Acid ◽

Protein Function ◽

Parasitic Nematode ◽

Binding Protein ◽

Plant Parasitic Nematode ◽

Retinol Binding Protein ◽

Aphelenchoides Besseyi ◽

Plant Parasitic

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Characterization of liver stellate cell retinyl ester storage

Biochemical Journal ◽

10.1042/bj3000793 ◽

1994 ◽

Vol 300 (3) ◽

pp. 793-798 ◽

Cited By ~ 26

Author(s):

G Trøen ◽

A Nilsson ◽

K R Norum ◽

R Blomhoff

Keyword(s):

Fatty Acid ◽

Binding Protein ◽

Stellate Cells ◽

The Body ◽

Retinol Binding Protein ◽

Storage Site ◽

Retinyl Ester ◽

Cellular Content ◽

Retinyl Esters ◽

Cultivation In Vitro

The stellate cells of the liver are the main storage site of retinyl esters in the body. During cultivation in vitro of stellate cells isolated from rat and rabbit livers were observed that the cells rapidly loose their retinyl ester content. Freshly isolated stellate cells contain about 144 nmol of total retinol/mg of protein, while cells cultivated for 14 days contained below 0.1 nmol/mg of protein. When 3-day-old cultures were incubated for 6 h with 2 microM retinol, the cellular content increased from 5.6 to approx. 9.4 nmol of total retinyl esters/mg of protein. In contrast, little retinyl ester accumulated in 10-20-day-old cultures incubated with 2 microM retinol. At 50 microM retinol, however, the retinyl ester level did increase both with 3-day-old cultures and 10-20-day-old cultures. In parallel experiments with cultured fibroblasts esterification characteristics similar to those seen in older cultures of stellate cells were observed. When 10-day-old cultures of stellate cells were incubated with retinol alone, or in combination with palmitic acid, linoleic acid or oleic acid, the total storage of retinyl esters increased by 20-150%. In most cases, the fatty acid supplemented in the medium was found to be the dominant fatty acid esterified with retinol. Cultures of stellate cells were then exposed to a physiological concentration (1.3 microM) of radioactive retinol free in solution or bound to retinol-binding protein. With 3-day-old cultures, as well as older cultures, the cellular content of unesterified retinol was 10-20 times higher when free retinol was added compared with addition of retinol bound to retinol-binding protein. However, 2-3-fold as much radioactive retinyl esters were recovered in cells incubated with retinol-retinol-binding protein compared with retinol free in solution. These results show that retinol delivered to stellate cells from retinol-binding protein is preferentially esterified, and that the complex is handled differently to free retinol by the stellate cells.

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Cellular retinol-binding protein type III is a PPARγ target gene and plays a role in lipid metabolism

AJP Endocrinology and Metabolism ◽

10.1152/ajpendo.90464.2008 ◽

2008 ◽

Vol 295 (6) ◽

pp. E1358-E1368 ◽

Cited By ~ 35

Author(s):

Cynthia F. Zizola ◽

Gary J. Schwartz ◽

Silke Vogel

Keyword(s):

Adipose Tissue ◽

Fatty Acid ◽

Lipid Metabolism ◽

Free Fatty Acid ◽

Target Gene ◽

Binding Protein ◽

Retinol Binding Protein ◽

Wild Type ◽

Type Iii ◽

Cellular Retinol Binding Protein

Cellular retinol-binding protein (CRBP) type III (CRBP-III) belongs to the family of intracellular lipid-binding proteins, which includes the adipocyte-binding protein aP2. In the cytosol, CRBP-III binds retinol, the precursor of retinyl ester and the active metabolite retinoic acid. The goal of the present work is to understand the regulation of CRBP-III expression and its role in lipid metabolism. Using EMSAs, luciferase reporter assays, and chromatin immunoprecipitation assays, we found that CRBP-III is a direct target of peroxisome proliferator-activated receptor-γ (PPARγ). Moreover, CRBP-III expression was induced in adipose tissue of mice after treatment with the PPARγ agonist rosiglitazone. To examine a potential role of CRBP-III in regulating lipid metabolism in vivo, CRBP-III-deficient (C-III-KO) mice were maintained on a high-fat diet (HFD). Hepatic steatosis was decreased in HFD-fed C-III-KO compared with HFD-fed wild-type mice. These differences were partly explained by decreased serum free fatty acid levels and decreased free fatty acid efflux from adipose tissue of C-III-KO mice. In addition, the lack of CRBP-III was associated with reduced food intake, increased respiratory energy ratio, and altered body composition, with decreased adiposity and increased lean body mass. Furthermore, expression of genes involved in mitochondrial fatty acid oxidation in brown adipose tissue was increased in C-III-KO mice, and C-III-KO mice were more cold tolerant than wild-type mice fed an HFD. In summary, we demonstrate that CRBP-III is a PPARγ target gene and plays a role in lipid and whole body energy metabolism.

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Diet-related variation in cellular retinol-binding protein type II gene expression in rat jejunum

British Journal Of Nutrition ◽

10.1079/bjn20051575 ◽

2005 ◽

Vol 94 (6) ◽

pp. 890-895 ◽

Cited By ~ 5

Author(s):

Kazuhito Suruga ◽

Masaaki Kitagawa ◽

Hiromitsu Yasutake ◽

Sachiko Takase ◽

Toshinao Goda

Keyword(s):

Gene Expression ◽

Fatty Acid ◽

Binding Protein ◽

Dietary Fatty Acids ◽

Retinol Binding Protein ◽

Rat Jejunum ◽

Type Ii ◽

Feeding Period ◽

Related Variation ◽

Cellular Retinol Binding Protein

Cellular retinol-binding protein type II (CRBPII) is involved in the transport of vitamin A and its metabolism in the small intestine. In the present study, we demonstrated diet-related variations in CRBPII expression in rat jejunum. The CRBPII protein and mRNA levels increased in parallel after the start of feeding period regardless of whether the feeding period was restricted to the hours of darkness or of light. In addition, this variation was observed in the rats fed high-fat diet or low-fat diets, but not in those fed a fat-free diet or in fasted rats. A similar diet-induced variation was seen in the mRNA of liver-type fatty acid-binding protein in rat jejunum. In the transient transfection experiment, unsaturated fatty acid increased rat CRBPII gene promoter activity via the PPARα/retinoid X receptor-α heterodimer. Taken together, these results suggest that the diet-related variation in CRBPII expression in rat jejunum may be brought about by the transcriptional induction of CRBPII gene expression mainly triggered by dietary fatty acids.

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