Ursuliak Z, Clemens J C, Dixon J E, Price J V
Institute of Molecular Biology and Biochemistry, Simon Fraser University, Burnaby, BC, Canada.
Mech Dev. 1997 Jul;65(1-2):19-30. doi: 10.1016/s0925-4773(97)00046-4.
DPTP61F is a non-receptor protein tyrosine phosphatase that is expressed during Drosophila oogenesis and embryogenesis. DPTP61F transcripts are alternatively spliced to produce two isoforms of the protein which are targeted to different subcellular locations. DPTP61Fn accumulates in the nucleus, and DPTP61Fm associates with the membranes of the reticular network and the mitochondria. We have examined the spatial and temporal expression of the two alternative transcripts of dptp61F during Drosophila embryogenesis. Our observations indicate that the two isoforms are expressed in distinct patterns. The DPTP61Fn transcript is expressed in the mesoderm and neuroblast layer during germband extension and later in the gut epithelia. In comparison, the transcript encoding DPTP61Fm accumulates in 16 segmentally repeated stripes in the ectoderm during germband extension. These stripes are flanked by, and adjacent to, the domains of engrailed and wingless gene expression in the anterior/posterior axis. In stage 10 embryos, the domains of DPTP61Fm transcript accumulation are wedge shaped and roughly coincide with the area lateral to the denticle belts that will give rise to naked cuticle. The DPTP61Fm transcript is also expressed later in embryogenesis in the central nervous system. The segmental modulation of DPTP61Fm transcript accumulation in the A/P axis of the germband is regulated by the pair-rule genes, and the intrasegmental pattern of transcript accumulation is regulated by the segment polarity genes.
DPTP61F是一种非受体蛋白酪氨酸磷酸酶，在果蝇卵子发生和胚胎发生过程中表达。DPTP61F转录本经过可变剪接产生两种蛋白异构体，它们定位于不同的亚细胞位置。DPTP61Fn在细胞核中积累，而DPTP61Fm与网状网络和线粒体的膜相关联。我们研究了果蝇胚胎发生过程中dptp61F两种可变转录本的时空表达。我们的观察结果表明，这两种异构体以不同的模式表达。DPTP61Fn转录本在胚带延伸期间在中胚层和神经母细胞层中表达，随后在肠道上皮中表达。相比之下，编码DPTP61Fm的转录本在胚带延伸期间在外胚层中以16个节段重复的条带形式积累。这些条带在前/后轴上与engrailed和wingless基因表达的区域相邻并位于其两侧。在10期胚胎中，DPTP61Fm转录本积累的区域呈楔形，大致与齿状带外侧将产生裸表皮的区域重合。DPTP61Fm转录本在胚胎发生后期也在中枢神经系统中表达。胚带A/P轴上DPTP61Fm转录本积累的节段性调节由成对规则基因调控，转录本积累的节内模式由节段极性基因调控。
