<i>Fryl</i> deficiency is associated with defective kidney development and function in mice

Byun, Yong-Sub,Kim, Eun-Kyoung,Araki, Kimi,Yamamura, Ken-ichi,Lee, Kihoon,Yoon, Won-Kee,Won, Young-Suk,Kim, Hyoung-Chin,Choi, Kyung-Chul,Nam, Ki-Hoan SAGE Publications 2018 Experimental biology and medicine Vol.243 No.5

<P> FRY like transcription coactivator ( Fryl) gene located on chromosome 5 is a paralog of FRY microtubule binding protein ( Fry) in vertebrates. It encodes a protein with unknown functions. Fryl gene is conserved in various species ranging from eukaryotes to human. Although there are several reports on functions of Fry gene, functions of Fryl gene remain unclear. A mouse line containing null mutation in Fryl gene by gene trapping was produced in this study for the first time. The survival and growth of Fryl<SUP>−/−</SUP> mice were observed. Fryl gene expression levels in mouse tissues were determined and histopathologic analyses were conducted. Most Fryl<SUP>−/−</SUP> mice died soon after birth. Rare Fryl<SUP>−/−</SUP> survivors showed growth retardation with significantly lower body weight compared to their littermate controls. Although they could breed, more than half of Fryl<SUP>−/−</SUP> survivors died of hydronephrosis before age 1. No abnormal histopathologic lesion was apparent in full-term embryo or adult tissues except the kidney. Abnormal lining cell layer detachments from walls of collecting and convoluted tubules in kidneys were apparent in Fryl<SUP>−/−</SUP> neonates and full-term embryos. Fryl gene was expressed in renal tubular tissues including the glomeruli and convoluted and collecting tubules. This indicates that defects in tubular systems are associated with Fryl functions and death of Fryl<SUP>−/−</SUP> neonates. Fryl protein is required for normal development and functional maintenance of kidney in mice. This is the first report of in vivo Fryl gene functions. </P><B>Impact statement</B><P> FRY like transcription coactivator ( Fryl) gene is conserved in various species ranging from eukaryotes to human. It expresses a protein with unknown function. We generated a Fryl gene mutant mouse line and found that most homozygous mice died soon after their birth. Rare Fryl<SUP>−/−</SUP> survivors showed growth retardation with significantly lower body weight compared to their littermate controls. Although they could breed, more than half of Fryl<SUP>−/−</SUP> survivors died of hydronephrosis before age 1. Full-term mutant embryos showed abnormal collecting and convoluted tubules in kidneys where Fryl gene was expressed. Collectively, these results indicate that Fryl protein is required for normal development and functional maintenance of kidney in mice. To the best of our knowledge, this is the first report on in vivo Fryl gene functions. </P>

Interaction of CD99 with Its Paralog CD99L2 Positively Regulates CD99L2 Trafficking to Cell Surfaces

Nam, Giri,Lee, Young-Kwan,Lee, Hye Yeong,Ma, Min Jung,Araki, Masatake,Araki, Kimi,Lee, Seungbok,Lee, Im-Soon,Choi, Eun Young The American Association of Immunologists, Inc. 2013 JOURNAL OF IMMUNOLOGY Vol.191 No.11

<P>Mouse CD99 and its paralog CD99-like 2 (CD99L2) are surface proteins implicated in cellular adhesion and migration. Although their distributions overlap in a wide variety of cells, their physical/functional relationship is currently unknown. In this study, we show the interaction between the two molecules and its consequence for membrane trafficking of mouse (m)CD99L2. The interaction was analyzed by bimolecular fluorescence complementation, immunoprecipitation, and fluorescence resonance energy transfer assays. When coexpressed, mCD99 formed heterodimers with mCD99L2, as well as homodimers, and the heterodimers were localized more efficiently at the plasma membrane than were the homodimers. Their interaction was cytoplasmic domain–dependent and enhanced mCD99L2 trafficking to the plasma membrane regardless of whether it was transiently overexpressed or endogenously expressed. Surface levels of endogenous mCD99L2 were markedly low on thymocytes, splenic leukocytes, and CTL lines derived from CD99-deficient mice. Importantly, the surface levels of mCD99L2 on mCD99-deficient cells recovered significantly when wild-type mCD99 was exogenously introduced, but they remained low when a cytoplasmic domain mutant of mCD99 was introduced. Our results demonstrate a novel role for mCD99 in membrane trafficking of mCD99L2, providing useful insights into controlling transendothelial migration of leukocytes.</P>

WDR11‐mediated Hedgehog signalling defects underlie a new ciliopathy related to Kallmann syndrome

Kim, Yeon‐,Joo,Osborn, Daniel PS,Lee, Ji‐,Young,Araki, Masatake,Araki, Kimi,Mohun, Timothy,Kä,nsä,koski, Johanna,Brandstack, Nina,Kim, Hyun‐,Taek,Miralles, Francesc,Kim, Cheo John Wiley and Sons Inc. 2018 EMBO reports Vol.19 No.2

<P><B>Abstract</B></P><P>WDR11 has been implicated in congenital hypogonadotropic hypogonadism (CHH) and Kallmann syndrome (KS), human developmental genetic disorders defined by delayed puberty and infertility. However, WDR11's role in development is poorly understood. Here, we report that WDR11 modulates the Hedgehog (Hh) signalling pathway and is essential for ciliogenesis. Disruption of WDR11 expression in mouse and zebrafish results in phenotypic characteristics associated with defective Hh signalling, accompanied by dysgenesis of ciliated tissues. <I>Wdr11</I>‐null mice also exhibit early‐onset obesity. We find that WDR11 shuttles from the cilium to the nucleus in response to Hh signalling. WDR11 regulates the proteolytic processing of GLI3 and cooperates with the transcription factor EMX1 in the induction of downstream Hh pathway gene expression and gonadotrophin‐releasing hormone production. The CHH/KS‐associated human mutations result in loss of function of WDR11. Treatment with the Hh agonist purmorphamine partially rescues the WDR11 haploinsufficiency phenotypes. Our study reveals a novel class of ciliopathy caused by WDR11 mutations and suggests that CHH/KS may be a part of the human ciliopathy spectrum.</P>

IGSF4 is a novel TCR ζ-chain–interacting protein that enhances TCR-mediated signaling

Kim, Hye-Ran,Jeon, Byeong-Hun,Lee, Hyun-Su,Im, Sin-Hyeog,Araki, Masatake,Araki, Kimi,Yamamura, Ken-ichi,Choi, Suck-Chei,Park, Do-Sim,Jun, Chang-Duk The Rockefeller University Press 2011 The Journal of experimental medicine Vol.208 No.12

<P>Immunoglobulin superfamily member 4 (IGSF4) is a known ligand of CRTAM, a receptor expressed in activated NKT and CD8<SUP>+</SUP> T cells, but its function in T cell immunity has not been elucidated. In this study, we show that IGSF4 directly interacts with the T cell receptor (TCR) ζ-chain and enhances TCR signaling by enhancing ζ-chain phosphorylation. Ectopic overexpression of <I>IGSF4</I> enhances TCR-mediated T cell activation. In contrast, <I>IGSF4</I> knockdown shows a dramatic decrease in markers associated with T cell activation compared with those in control small interfering RNA. The transmembrane domain is essential for TCR ζ-chain association and clustering to the immunological synapse, and the ectodomain is associated with T cell interaction with antigen-presenting cells (APCs). <I>IGSF4</I>-deficient mice have impaired TCR-mediated thymocyte selection and maturation. Furthermore, these mice reveal attenuated effector T cell functions accompanied by defective TCR signaling. Collectively, the results indicate that IGSF4 plays a central role in T cell functioning by dual independent mechanisms, control of TCR signaling and control of T cell–APC interaction.</P>

NSrp70 is a novel nuclear speckle-related protein that modulates alternative pre-mRNA splicing <i>in vivo</i>

Kim, Young-Dae,Lee, Jung-Yoon,Oh, Kyu-Man,Araki, Masatake,Araki, Kimi,Yamamura, Ken-ichi,Jun, Chang-Duk Oxford University Press 2011 Nucleic acids research Vol.39 No.10

<P>Nuclear speckles are known to be the storage sites of mRNA splicing regulators. We report here the identification and characterization of a novel speckle protein, referred to as NSrp70, based on its subcellular localization and apparent molecular weight. This protein was first identified as CCDC55 by the National Institutes of Health Mammalian Gene Collection, although its function has not been assigned. NSrp70 was colocalized and physically interacted with SC35 and ASF/SF2 in speckles. NSrp70 has a putative RNA recognition motif, the RS-like region, and two coiled-coil domains, suggesting a role in RNA processing. Accordingly, using CD44, Tra2β1 and Fas constructs as splicing reporter minigenes, we found that NSrp70 modulated alternative splice site selection <I>in vivo</I>. The C-terminal 10 amino acids (531–540), including <SUP>536</SUP>RD<SUP>537</SUP>, were identified as a novel nuclear localization signal, and the region spanning 290–471 amino acids was critical for speckle localization and binding to SC35 and ASF/SF2. The N-terminal region (107–161) was essential for the pre-mRNA splicing activity. Finally, we found that knockout of <I>NSrp70</I> gene in mice led to a lack of progeny, including fetal embryos. Collectively, we demonstrate that NSrp70 is a novel splicing regulator and essentially required early stage of embryonic development.</P>

CD99-dependent expansion of myeloid-derived suppressor cells and attenuation of graft-versus-host disease

Park, Hyo Jin,Byun, Dahye,Lee, An Hi,Kim, Ju Hyun,Ban, Young Larn,Araki, Masatake,Araki, Kimi,Yamamura, Ken-ichi,Kim, Inho,Park, Seong Hoe,Jung, Kyeong Cheon Springer-Verlag 2012 Molecules and cells Vol.33 No.3

CD99-Dependent Expansion of Myeloid-Derived Suppressor Cells and Attenuation of Graft-Versus-Host Disease

Hyo Jin Park,정경천,Dahye Byun,이안희,Ju Hyun Kim,Young Larn Ban,Masatake Araki,Kimi Araki,Ken-ichi Yamamura,김인호,박성회 한국분자세포생물학회 2012 Molecules and cells Vol.33 No.3

CD99 is involved in many cellular events, such as the generation of Hodgkin and Reed-Sternberg cells, T cell co-stimulation, and leukocyte transendothelial migration. However, these studies have been limited to in vitro or in vivo experiments using CD99-deficient cell lines or anti-CD99 antibodies. In the present study, using CD99-deficient mice established by the exchangeable gene trap method, we investigated the physiologic function of murine CD99. In a B6 splenocytes  bm12 graft-versus-host disease model, wild-type cells were minimally lethal, whereas all mice that received CD99-deficient donor cells developed an early and more severe pathology. Graft-versus-host disease in these mice was associated with insufficient expansion of myeloid-derived suppressor cells. This was confirmed by experiments illustrating that the injection of wild-type donor cells depleted of Mac-1+ cells led to an almost identical disease course as the CD99-deficient donor system. Therefore, these results suggest that CD99 plays a crucial role in the attenuation of graft-versus-host disease by regulating the expansion of myeloid-derived suppressor cells.