Saghizadeh Mehrnoosh, Gribanova Yekaterina, Akhmedov Novrouz B, Farber Debora B
Jules Stein Eye Institute, UCLA, Los Angeles, CA, USA.
Mol Vis. 2011;17:2011-8. Epub 2011 Jul 21.
ZBED4, a protein in cones and Müller cells of human retina, may play important functions as a transcriptional activator of genes expressed in those cells or as a co-activator/repressor of their nuclear hormone receptors. To begin investigating these potential roles of ZBED4, we studied the developmental expression and localization of both the Zbed4 mRNA and protein of mouse retina.
northern blots showed the presence of Zbed4 mRNA in retina and other mouse tissues, and western blots showed the nuclear and cytoplasmic expression of Zbed4 at different developmental times. Antibodies against Zbed4 and specific retinal cell markers were used for retinal immunohistochemistry.
Zbed4 mRNA was present at different levels in all the mouse tissues analyzed. The Zbed4 protein was barely detectable at embryonic day (E)14.5 but was clearly seen at E16 at both retinal outer and vitreal borders and throughout the retina by E18 and postnatal day 0 (P0). Thereafter, Zbed4 expression was more restricted to the inner retina. While ZBED4 is localized in cones and endfeet of Müller cells of human retina, in adult mouse retina Zbed4 is only detected in Müller cell endfeet and processes. The same localization of Zbed4 was observed in rat retina. In early development, Zbed4 is mainly present in the nuclear fraction of the mouse retina, and in adulthood it becomes more enriched in the cytoplasmic fraction.
The patterns of spatial and temporal expression of Zbed4 in the mouse retina suggest a possible involvement of this protein in retinal morphogenesis and Müller cell function.
ZBED4是一种存在于人类视网膜视锥细胞和穆勒细胞中的蛋白质，它可能作为这些细胞中表达基因的转录激活因子，或者作为其核激素受体的共激活因子/阻遏因子发挥重要作用。为了开始研究ZBED4的这些潜在作用，我们研究了小鼠视网膜中Zbed4 mRNA和蛋白质的发育表达及定位。
Northern印迹显示Zbed4 mRNA存在于视网膜和其他小鼠组织中，Western印迹显示Zbed4在不同发育时期的细胞核和细胞质中均有表达。使用针对Zbed4和特定视网膜细胞标志物的抗体进行视网膜免疫组织化学分析。
在所有分析的小鼠组织中，Zbed4 mRNA均以不同水平存在。在胚胎第14.5天（E14.5）几乎检测不到Zbed4蛋白，但在E16时在视网膜外层和玻璃体边界处清晰可见，到E18和出生后第0天（P0）时在整个视网膜中均可见。此后，Zbed4的表达更局限于视网膜内层。虽然ZBED4定位于人类视网膜的视锥细胞和穆勒细胞的终足，但在成年小鼠视网膜中，仅在穆勒细胞终足和突起中检测到Zbed4。在大鼠视网膜中也观察到Zbed4的相同定位。在早期发育中，Zbed4主要存在于小鼠视网膜的细胞核部分，而在成年期，它在细胞质部分中更为富集。
Zbed4在小鼠视网膜中的时空表达模式表明该蛋白可能参与视网膜形态发生和穆勒细胞功能。
