APOA4转录和翻译主要在肠道和运输脂肪组织通过循环。(A) APOA4基因表达小鼠空肠和肝脏组织,但不是在性腺的脂肪组织和肾脏。rt - pcr ApoA4和β-actin进行总mRNA空肠隔绝,肝脏,从男性和女性的性腺的脂肪和肾组织129 x1 / SvJ WT老鼠每性(n = 3)。ApoA4水平与β-actin规范化水平和数据提出了褶皱变化在空肠ApoA4 mRNA水平正常化。见附加图S1。(B)存在APOA4蛋白组织的WT但不是APOA4−−老鼠。总蛋白(40µg)从空肠,肝脏,附睾的脂肪和肾组织和血浆(10μg)分离与anti-APOA4抗体通过sds - page和探索。污点被剥夺和探测anti-β-actin加载控制用于规范化。代表免疫印迹图像显示从WT APOA4蛋白在所有组织的存在,但不是APOA4−−/老鼠(n = 3 /组);这些发现也证实了使用的抗体的特异性。 (C-E) Representative immunofluorescence confocal images of APOA4 immunoreactivity (IR) in mouse gonadal fat tissues. Epididymal fat from male and periovarian fat from female mice were harvested, fixed, paraffin embedded, sectioned and stained with anti-APOA4 and anti-caveolin-1 (n = 2 technical and 3 biological replicates). Scale bar: 50 μm. (C) APOA4 immunoreactivity (APOA4-IR) was present at the cell surface of adipocytes in a discrete manner in male and female WT mice (arrows) and in the vasculature (inset: arrowhead), (D) no APOA4-IR was detected in ApoA4−/− mice, thereby also confirming specificity of the antibody used. (E) I.p. injection of r-m-APOA4 (5 μg/g body weight) in ApoA4−/− mice resulted in APOA4 uptake in gonadal fat tissues with similar pattern of localization of APOA4-IR in adipocytes as that in WT mice (arrows show discrete cell surface expression). (F) Apo-A-IV-IR co-localized with the adipocyte cell surface marker caveolin-1 (Merge, yellow arrows), but not in the vasculature (white arrowhead), confirming that exogenous APOA4 is targeted to the appropriate cell types. Scale bar: 50 μm and 10 µm. Credit: DOI: 10.1038/s41598-021-92711-0
