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Glial cell missing 1 (GCM1) transcription factor regulates placental cell fusion into the syncytiotrophoblast. Caspase-14 is proteolytically activated to mediate filaggrin processing during keratinocyte differentiation. Interestingly, altered expression of nonactivated caspase-14 proenzyme is associated with tumorigenesis and diabetic retinopathy, suggesting that caspase-14 may perform physiological functions independently of its protease activity. Here, we performed tandem affinity purification coupled with mass spectrometry analysis to identify caspase-14 proenzyme as a GCM1-interacting protein that suppresses GCM1 activity and syncytiotrophoblast differentiation. Immunohistochemistry revealed that caspase-14 and GCM1 colocalize to placental cytotrophoblast cells at 8 wk of gestation and syncytiotrophoblast layer at term. Further, we demonstrated that caspase-14 mRNA level is decreased by 40% in placental BeWo cells treated with forskolin (FSK). To the contrary, stimulation of GCM1-regulated placental cell fusion and human chorionic gonadotropin β (hCGβ) expression by FSK is enhanced by caspase-14 knockdown. Indeed, GCM1 protein level is increased by 40% in the caspase-14-knockdown BeWo cells. Because GCM1 is stabilized by acetylation, we subsequently showed that caspase-14 impedes the interaction between GCM1 and cAMP response element-binding protein (CREB)-binding protein (CBP) to suppress CBP-mediated acetylation and transcriptional coactivation of GCM1. Therefore, caspase-14 can suppress placental cell differentiation through down-regulation of GCM1 activity.

InGaN-based light-emitting diodes (LEDs) with inverted pyramidal structures at their GaN/patterned-sapphire interfaces were fabricated by laser decomposition and wet crystallographic etching. Partially roughening the LED structure increased the light output power of the by 21% enhancement at an operating current of 20mA over that of a non-treated LED structure. The transmittance of the roughened LED structure (10.5%) was lower than that of a non-treated LED structure (20.3%) at 447nm because the incident light was mostly reflected and scattered by the patterned-sapphire structure and by the roughened structure at the GaN/sapphire interface. The light emission intensity in the laser-treated striped region, with the roughened N-face GaN surface was higher than that in the non-treated patterned sapphire region. The InGaN structure with the roughened inverted pyramidal structure increased the light extraction efficiency of nitride-based LEDs.Gallium nitride materials have attracted much interest in the development of optoelectronic devices such as white light-emitting diodes 1 (LEDs) and laser diodes. Nevertheless, bright blue LEDs require higher internal and external quantum efficiencies. The low external quantum efficiency of InGaN-based LEDs is caused by the large difference between the refractive indexes of the GaN layer and the surrounding air ( n∼1.5). Bottom-patterned Al 2 O 3 substrates, 2 roughened p-type GaN:Mg surface, 3 the formation of photonic crystal structures, 4 amorphous titanium oxide films with porous structures and a graded refractive-index, 5 two-floor air prism arrays as embedded reflectors, 6 overcut side-holes that are formed by wet etching, 7 and anisotropically etched GaN-sapphire interfaces, 8 have all been utilized to increase the light-extraction efficiency of InGaN-based LEDs on Al 2 O 3 substrates. Fujii et al. 9 reported that a laser-lift-off technique that was followed by an anisotropic etching process to roughen the surface of an n-side-up GaN-based LED with a hexagonal ''conelike'' surface, increased extraction efficiency. Structures of InGaN-based LEDs that promote light extraction have also been formed using pulselaser fabrication processes. 10-13 Lee et al. 14 increased the output power of an InGaN-based LED by reducing both the thermal damage to the sapphire substrate, along with the consequently formed debris, using femtosecond laser scribing.In this work, roughened inverted-pyramidal structures of InGaN LEDs were observed at the top and the bottom of the patternedsapphire substrate via a laser decomposition process and a wet etching process. The InGaN LED structure comprised a patterned sapphire substrate and a roughened structure that increased light extraction efficiency. A roughened N-face GaN surface was formed for high light extraction without using a conventional laser lift-off process. The optical properties, light-extraction efficiency, and far-field radiation pattern of the laser-treated LED structures were analyzed in detail. ExperimentalInGaN-based LED structures w...

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