Surace E M, Angeletti B, Ballabio A, Marigo V
Telethon Institute of Genetics and Medicine and the. Universitá Vita e Salute, San Raffaele, Milan, Italy.
Invest Ophthalmol Vis Sci. 2000 Dec;41(13):4333-7.
Mutations in the OA1 gene cause ocular albinism type 1 (OA1), an X-linked form of albinism affecting only the eye, with skin pigmentation appearing normal. To better understand the pathogenesis of this disease the time of onset and the pattern of expression of the mouse homolog of the OA1 gene were monitored during eye development. The localization of Oa1 mRNA was studied and compared with the expression of other genes involved in melanosomal biogenesis.
The Oa1 expression pattern during eye development and after birth was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and in situ hybridization. Localization of Oa1 mRNA was compared with TYROSINASE: (TYR:), pink-eyed dilution (p), and Pax2 expression patterns.
RT-PCR revealed that Oa1 expression began at embryonic day (E)10.5 and was maintained until adulthood. By in situ hybridization analysis Oa1 transcripts were detected in the retinal pigment epithelium (RPE) beginning at E10.5 in the dorsal part of the eyecup and in the same area where transcripts of other genes involved in pigmentation are found. Of note, the expression pattern of these genes was complementary to Pax2 expression, which was restricted to the ventral side of the optic cup. At later stages, expression of Oa1, TYR:, and p expanded to the entire RPE and ciliary body.
Oa1 expression can be detected at early stages of RPE development, together with other genes involved in pigmentation defects. Oa1 is likely to play an important function in melanosomal biogenesis in the RPE beginning during the earliest steps of melanosome formation.
OA1基因突变导致1型眼白化病（OA1），这是一种仅影响眼睛的X连锁白化病形式，皮肤色素沉着看起来正常。为了更好地理解这种疾病的发病机制，在眼睛发育过程中监测了OA1基因小鼠同源物的起始时间和表达模式。研究了Oa1 mRNA的定位，并与参与黑素小体生物发生的其他基因的表达进行了比较。
通过逆转录聚合酶链反应（RT-PCR）和原位杂交分析眼睛发育期间及出生后Oa1的表达模式。将Oa1 mRNA的定位与酪氨酸酶（TYR）、粉红眼稀释基因（p）和Pax2的表达模式进行比较。
RT-PCR显示Oa1表达在胚胎第（E）10.5天开始，并持续到成年期。通过原位杂交分析，在视杯背侧的E10.5开始于视网膜色素上皮（RPE）中检测到Oa1转录本，并且在发现其他参与色素沉着的基因转录本的相同区域中也检测到。值得注意的是，这些基因的表达模式与Pax2的表达互补，Pax2的表达仅限于视杯的腹侧。在后期，Oa1、TYR和p的表达扩展到整个RPE和睫状体。
在RPE发育的早期阶段可以检测到Oa1的表达，以及其他参与色素沉着缺陷的基因。Oa1可能在黑素小体形成的最早步骤开始时就在RPE的黑素小体生物发生中发挥重要作用。
