Functional analysis of the omega-6 fatty acid desaturase (CaFAD2) gene family of the oil seed crop Crambe abyssinica using RNAi-mediated gene silencing

J. Cheng, L. Zhu, E.M.J. Salentijn, B. Huang, J. Gruber, A.C. Dechesne, F.A. Krens, W. Qi, R.G.F. Visser, E.N. van Loo

Research output: Contribution to journalArticleAcademicpeer-review

11 Citations (Scopus)

Abstract

Background Crambe abyssinica produces high erucic acid (C22:1, 55-60 %) in the seed oil, which can be further increased by reduction of polyunsaturated fatty acid (PUFA) levels. The omega-6 fatty acid desaturase enzyme (FAD2) is known to be involved in PUFA biosynthesis. In crambe, three CaFAD2 genes, CaFAD2-C1, CaFAD2-C2 and CaFAD2-C3 are expressed. Results The individual effect of each CaFAD2 gene on oil composition was investigated through studying transgenic lines (CaFAD2-RNAi) for differential expression levels in relation to the composition of seed-oil. Six first generation transgenic plants (T1) showed C18:1 increase (by 6% to 10.5 %) and PUFA reduction (by 8.6% to 10.2 %). The silencing effect in these T1-plants ranged from the moderate silencing (40% to 50% reduction) of all three CaFAD2 genes to strong silencing (95% reduction) of CaFAD2-C3 alone. The progeny of two T1-plants (WG4-4 and WG19-6) was further analysed. Four or five transgene insertions are characterized in the progeny (T2) of WG19-6 in contrast to a single insertion in the T2 progeny of WG4-4. For the individual T2-plants of both families (WG19-6 and WG4-4), seed-specific silencing of CaFAD2-C1 and CaFAD2-C2 was observed in several individual T2-plants but, on average in both families, the level of silencing of these genes was not significant. A significant reduction in expression level (P <0.01) in both families was only observed for CaFAD2-C3 together with significantly different C18:1 and PUFA levels in oil. Conclusions CaFAD2-C3 expression is highly correlated to levels of C18:1 (r = -0.78) and PUFA (r = 0.75), which suggests that CaFAD2-C3 is the most important one for changing the oil composition of crambe.
Original languageEnglish
Article number146
JournalBMC Plant Biology
Volume13
DOIs
Publication statusPublished - 2013

Fingerprint

Crambe abyssinica
stearoyl-CoA desaturase
oilseed crops
omega-6 fatty acids
gene silencing
polyunsaturated fatty acids
seed oils
genes
oils
Crambe (Brassicaceae)
erucic acid
transgenes
transgenic plants
genetically modified organisms
biosynthesis
enzymes
seeds

Keywords

  • high oleic-acid
  • erucic-acid
  • brassica-napus
  • fad2 gene
  • fae1 gene
  • carrier protein
  • expression
  • suppression
  • metabolism
  • mutations

Cite this

@article{055e57ae7d964e75a19f29ea65569b25,
title = "Functional analysis of the omega-6 fatty acid desaturase (CaFAD2) gene family of the oil seed crop Crambe abyssinica using RNAi-mediated gene silencing",
abstract = "Background Crambe abyssinica produces high erucic acid (C22:1, 55-60 {\%}) in the seed oil, which can be further increased by reduction of polyunsaturated fatty acid (PUFA) levels. The omega-6 fatty acid desaturase enzyme (FAD2) is known to be involved in PUFA biosynthesis. In crambe, three CaFAD2 genes, CaFAD2-C1, CaFAD2-C2 and CaFAD2-C3 are expressed. Results The individual effect of each CaFAD2 gene on oil composition was investigated through studying transgenic lines (CaFAD2-RNAi) for differential expression levels in relation to the composition of seed-oil. Six first generation transgenic plants (T1) showed C18:1 increase (by 6{\%} to 10.5 {\%}) and PUFA reduction (by 8.6{\%} to 10.2 {\%}). The silencing effect in these T1-plants ranged from the moderate silencing (40{\%} to 50{\%} reduction) of all three CaFAD2 genes to strong silencing (95{\%} reduction) of CaFAD2-C3 alone. The progeny of two T1-plants (WG4-4 and WG19-6) was further analysed. Four or five transgene insertions are characterized in the progeny (T2) of WG19-6 in contrast to a single insertion in the T2 progeny of WG4-4. For the individual T2-plants of both families (WG19-6 and WG4-4), seed-specific silencing of CaFAD2-C1 and CaFAD2-C2 was observed in several individual T2-plants but, on average in both families, the level of silencing of these genes was not significant. A significant reduction in expression level (P <0.01) in both families was only observed for CaFAD2-C3 together with significantly different C18:1 and PUFA levels in oil. Conclusions CaFAD2-C3 expression is highly correlated to levels of C18:1 (r = -0.78) and PUFA (r = 0.75), which suggests that CaFAD2-C3 is the most important one for changing the oil composition of crambe.",
keywords = "high oleic-acid, erucic-acid, brassica-napus, fad2 gene, fae1 gene, carrier protein, expression, suppression, metabolism, mutations",
author = "J. Cheng and L. Zhu and E.M.J. Salentijn and B. Huang and J. Gruber and A.C. Dechesne and F.A. Krens and W. Qi and R.G.F. Visser and {van Loo}, E.N.",
year = "2013",
doi = "10.1186/1471-2229-13-146",
language = "English",
volume = "13",
journal = "BMC Plant Biology",
issn = "1471-2229",
publisher = "Springer Verlag",

}

TY - JOUR

T1 - Functional analysis of the omega-6 fatty acid desaturase (CaFAD2) gene family of the oil seed crop Crambe abyssinica using RNAi-mediated gene silencing

AU - Cheng, J.

AU - Zhu, L.

AU - Salentijn, E.M.J.

AU - Huang, B.

AU - Gruber, J.

AU - Dechesne, A.C.

AU - Krens, F.A.

AU - Qi, W.

AU - Visser, R.G.F.

AU - van Loo, E.N.

PY - 2013

Y1 - 2013

N2 - Background Crambe abyssinica produces high erucic acid (C22:1, 55-60 %) in the seed oil, which can be further increased by reduction of polyunsaturated fatty acid (PUFA) levels. The omega-6 fatty acid desaturase enzyme (FAD2) is known to be involved in PUFA biosynthesis. In crambe, three CaFAD2 genes, CaFAD2-C1, CaFAD2-C2 and CaFAD2-C3 are expressed. Results The individual effect of each CaFAD2 gene on oil composition was investigated through studying transgenic lines (CaFAD2-RNAi) for differential expression levels in relation to the composition of seed-oil. Six first generation transgenic plants (T1) showed C18:1 increase (by 6% to 10.5 %) and PUFA reduction (by 8.6% to 10.2 %). The silencing effect in these T1-plants ranged from the moderate silencing (40% to 50% reduction) of all three CaFAD2 genes to strong silencing (95% reduction) of CaFAD2-C3 alone. The progeny of two T1-plants (WG4-4 and WG19-6) was further analysed. Four or five transgene insertions are characterized in the progeny (T2) of WG19-6 in contrast to a single insertion in the T2 progeny of WG4-4. For the individual T2-plants of both families (WG19-6 and WG4-4), seed-specific silencing of CaFAD2-C1 and CaFAD2-C2 was observed in several individual T2-plants but, on average in both families, the level of silencing of these genes was not significant. A significant reduction in expression level (P <0.01) in both families was only observed for CaFAD2-C3 together with significantly different C18:1 and PUFA levels in oil. Conclusions CaFAD2-C3 expression is highly correlated to levels of C18:1 (r = -0.78) and PUFA (r = 0.75), which suggests that CaFAD2-C3 is the most important one for changing the oil composition of crambe.

AB - Background Crambe abyssinica produces high erucic acid (C22:1, 55-60 %) in the seed oil, which can be further increased by reduction of polyunsaturated fatty acid (PUFA) levels. The omega-6 fatty acid desaturase enzyme (FAD2) is known to be involved in PUFA biosynthesis. In crambe, three CaFAD2 genes, CaFAD2-C1, CaFAD2-C2 and CaFAD2-C3 are expressed. Results The individual effect of each CaFAD2 gene on oil composition was investigated through studying transgenic lines (CaFAD2-RNAi) for differential expression levels in relation to the composition of seed-oil. Six first generation transgenic plants (T1) showed C18:1 increase (by 6% to 10.5 %) and PUFA reduction (by 8.6% to 10.2 %). The silencing effect in these T1-plants ranged from the moderate silencing (40% to 50% reduction) of all three CaFAD2 genes to strong silencing (95% reduction) of CaFAD2-C3 alone. The progeny of two T1-plants (WG4-4 and WG19-6) was further analysed. Four or five transgene insertions are characterized in the progeny (T2) of WG19-6 in contrast to a single insertion in the T2 progeny of WG4-4. For the individual T2-plants of both families (WG19-6 and WG4-4), seed-specific silencing of CaFAD2-C1 and CaFAD2-C2 was observed in several individual T2-plants but, on average in both families, the level of silencing of these genes was not significant. A significant reduction in expression level (P <0.01) in both families was only observed for CaFAD2-C3 together with significantly different C18:1 and PUFA levels in oil. Conclusions CaFAD2-C3 expression is highly correlated to levels of C18:1 (r = -0.78) and PUFA (r = 0.75), which suggests that CaFAD2-C3 is the most important one for changing the oil composition of crambe.

KW - high oleic-acid

KW - erucic-acid

KW - brassica-napus

KW - fad2 gene

KW - fae1 gene

KW - carrier protein

KW - expression

KW - suppression

KW - metabolism

KW - mutations

U2 - 10.1186/1471-2229-13-146

DO - 10.1186/1471-2229-13-146

M3 - Article

VL - 13

JO - BMC Plant Biology

JF - BMC Plant Biology

SN - 1471-2229

M1 - 146

ER -