1. Identification of the Δ-6 Desaturase of Human Sebaceous Glands: Expression and Enzyme Activity 
Lan Ge, Joel S. Gordon, Charleen Hsuan, Kurt Stenn, Stephen M. Prouty 
Journal of Investigative Dermatology 
Volume 120, Issue 5, Pages (May 2003)
DOI: /j x
Copyright © 2003 The Society for Investigative Dermatology, Inc Terms and Conditions

2. Figure 1
Localization of Δ-6 desaturase/FADS2 mRNA and protein in human skin. Δ-6 desaturase/FADS2 mRNA localization in human scalp plug tissue (53-y-old male) using antisense (A, B, C) and sense (D) DIG-labeled riboprobes. Note the lack of staining of the central portion (asterisk) of the SG in (B) and the lack of staining of SG basal cells (arrow) in (C). Immunocytochemical detection of Δ-6 desaturase/FASDS2 protein in SG of human scalp biopsy (E, F, G). Note the lack of staining of the central portion (asterisk) of the SG in (E), and the lack of staining of SG basal cells (arrow) in (G). Preabsorbed antisera have no staining (F). Scale bars: (A), (B) 200 μm; (B), (E), (F) 100 μm; (C), (G) 30 μm.
Journal of Investigative Dermatology  , DOI: ( /j x)
Copyright © 2003 The Society for Investigative Dermatology, Inc Terms and Conditions

3. Figure 2
Northern analysis of Δ-6 desaturase/FADS2 mRNA. A human multiple tissue northern blot (left side) containing 2 μg of poly(A)+ RNA per lane (Origene Technologies) and a total RNA blot (right side) containing 15 μg per lane of human adrenal gland, chest skin, and scalp hair plugs (see Materials and Methods) were hybridized with a 32P-labeled probe from d6c14. hΔ-6 D indicates the single Δ-6 desaturase/FADS2 mRNA of 3.6 kb. Total RNA blot was stripped and hybridized with a 32P-labeled GAPDH cDNA probe as a loading control.
Journal of Investigative Dermatology  , DOI: ( /j x)
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4. Figure 3
Southern blot analysis of human Δ-6 desaturase/FADS2. Samples of human genomic DNA (10 μg) digested with restriction endonuclease BamH I, EcoR I, EcoR V, Hind III, Kpn I, and Pst I, Sac I, and Xho I were electrophoresed, blotted, and hybridized with 32P-labeled probe from clone d6c14. Markers are Hind III digest of phage λ; sizes in kb are indicated.
Journal of Investigative Dermatology  , DOI: ( /j x)
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5. Figure 4
Schemes of Δ-6 desaturase/FADS2 enzyme reactions. Δ-6 desaturase/FADS2 enzyme activity of the PUFA-type (A) where substrates are essential fatty acids of the n-6 family (linoleate) and n-3 family (α-linolenate) and the products are the PUFAs γ-linolenate and stearidonate, respectively. The position of the Δ-6 desaturated double bond is indicated in red. The sebaceous-type Δ-6 desaturation reaction (B) introduces a single cis double bond in the saturated fatty acid palmitate to produce the mono-unsaturated fatty acid sapienate.
Journal of Investigative Dermatology  , DOI: ( /j x)
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6. Figure 5
Fatty acid analysis of human sebaceous lipids. (A) Sebum was collected from the forehead of an adult male volunteer and the fatty acids were saponified and derivatized as described in Materials and Methods prior to analysis by HPLC (blue). Derivatized palmitoleate (16:1 (Δ9)) was added to a sample from a second individual (red). Sapienate (16:1 (Δ6)) was identified by the expected slight increase in retention time of a Δ-6 relative to a Δ-9 fatty acid. (B) The saponified and derivatized fatty acids from an adult human male sebum sample were separated by HPLC. The resulting chromatogram (solid line) was aligned with a sequentially run chromatogram of a mixture of known derivatized fatty acid standards (dashed line), including 16:1 (Δ-6), palmitate (16:0), oleate (18:1 (Δ-9)), and stearate (18:0). Retention time is on the x axis and detector response (ultraviolet absorbance) is on the y axis.
The chromatograph reproduced that of two other individuals.
Journal of Investigative Dermatology  , DOI: ( /j x)
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7. Figure 6
Catalysis of the PUFA-type and sebaceous-type reactions by human Δ-6 desaturase/FASD2. (A) ER-CHO cell lines stably transfected with either the human Δ-6 desaturase/FADS2 ORF (red) or vector (blue) were treated with 14C linoleate [18:2 (Δ9, 12)]. After lipid extraction followed by saponification and derivatization, the fatty acids were analyzed by HPLC. Retention time is on the horizontal axis and response of the radioactivity detector is on the vertical axis. 20:3 (Δ8, 11, 14), dihomo-γ-linolenate; 20:4 (Δ5, 8, 11, 14), arachidonic acid. The chromatograph is representative of that of five independent incubations. (B) ER-CHO cell lines stably transfected with either the human Δ-6 desaturase/FADS2 ORF (hΔ-6 D) (middle panel) or vector (top panel) were treated with 14C palmitate (16:0), followed by lipid extraction and HPLC analysis of total fatty acids. HΔ-6 D cells were also treated with 14C palmitate plus 100 μM of 9-thia stearate, a Δ-9 desaturase inhibitor (lower panel). Retention time is on the horizontal axis and detector response (red, dpm; green, ultraviolet absorbance) is on the vertical axis. Blue line indicates the derivatized sapienate standard that was added to the fatty acid sample prior to loading on the HPLC column. Labels are as indicated in Figure 6(a). The chromatograph is representative of that of three independent incubations.
Journal of Investigative Dermatology  , DOI: ( /j x)
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