Receptor tyrosine kinase c-Kit, a marker found on interstitial cells of Cajal (ICCs), is expressed in Leydig cells, which are testicular interstitial cells. The expression of other ICC markers has not yet been reported. In this study, we investigated the expression of c-Kit and anoctamin 1 (ANO1), another ICC marker, in mouse testes. In addition, the relationship between c-Kit and ANO1 expression and Leydig cell function was investigated. We observed that c-Kit and ANO1 were predominantly expressed in mouse Leydig cells. The mRNA and protein of c-Kit and ANO1 were expressed in TM3, a mouse Leydig cell line. LH induced an increase in intracellular Ca2+ concentration, membrane depolarization, and testosterone secretion, whereas these signals were inhibited in the presence of c-Kit and ANO1 inhibitors. These results show that c-Kit and ANO1 are expressed in Leydig cells and are involved in testosterone secretion. Our findings suggest that Leydig cells may act as ICCs in testosterone secretion.

Insect cuticle tanning (pigmentation and sclerotization) is a complex and vital physiological process that begins with tyrosine and is responsible for production of both melanin- and quinoid-type pigments. In addition, these quinones undergo isomerization to quinone methides and cross-linking reactions with cuticular proteins for cuticle sclerotization. In this study, we studied the functions of TmDDC and TmY-y as well as TmNAT1, TmADC and Tmebony from Tenebrio molitor, which are involved in the tyrosine-derived melanin- and quinoid-type pigment productions, respectively. The temporal and spatial expression patterns of the genes were analyzed by real-time PCR. RNA interference was performed to understand the genetic regulation and molecular mechanism underlying the darkening and hardening of beetle cuticle.

The multicolored Asian ladybeetle Harmonia axyridis is characterized by polymorphism of the elytral pattern. Melanization in Harmonia axyridis is crucial for their elytral coloration, but the molecular mechanisms are not fully understood in this species. Tyrosine hydroxylase (TH) and dopa decarboxylase (DDC), two key enzymes in the melanin pathway, convert tyrosine and dopa into dopa and dopamine, respectively. In this study, it was to determine the role of TH and DDC of Harmonia axyridis (HaTH and HaDDC) in body and wing pigmentaion produced via melanin pathway. The cDNA sequences of HaTH and HaDDC were cloned to perform RNAi-based functional analysis. Injected dsRNA to the 4th larvae caused knockdown of target genes, and it was verified by quantative realtime PCR. Both TH and DDC RNAi adult show loss of black pigmentation in their body and wing pigmentaion. These results is expected to be helpful to investigate polymorphism by melanin pigment in Harmonia axyridis.

Insect cuticle/exoskeleton covering the entire external surface of the body is essential for protecting insects from various environmental stresses. Tyrosine metabolism plays a major role in not only the darkening of cuticle but also its hardening. In this work, we have focused on the functional analysis of nine genes involved in tyrosine-mediated cuticle tanning (pigmentation and sclerotization) pathway in Tenebrio molitor, which has a unique adult cuticle coloration, dark/black dorsal thorax and elytron, and reddish ventral thorax and abdomen. The temporal and spatial expression patterns of the genes were analyzed by real-time PCR, and RNA interference (RNAi) was performed to study the functional importance of these genes in cuticle coloration and/or hardening in T. molitor. This work was supported by NRFs (NRF-2015R1A2A2A01006614 and NRF-2015R1A6A3A04060323).

Phosphorylation of proteins is a post-translational modification process which plays a significant role in a wide range of cellular processes. Addition or removal of phosphate groups result in conformational changes in proteins leading either to their activation or inactivation. Tyrosine phosphorylation of protein is associated with sperm function in several mammalian species. The control of this process may via the changes in cyclic adenosine monophosphate (cAMP); the changes in cAMP levels that occur in the spermatozoa regulate protein kinase A (PKA) activity which, in turn, leads to the tyrosine phosphorylation of protein substrates by either the activation of sperm tyrosine kinases and/or the inhibition of phosphoprotein phosphatases. Cyclic nucleotides, in particular, cAMP, are important regulators of various maturation events in sperm including capacitation and motility. Interestingly, some environmental chemicals (ECs) may exert broader endocrine disrupting effects through possible modulation of cAMP/PKA second messenger systems. Otherwise, because the mature spermatozoa are transcriptionally inactive, therefore the study of sperm proteins phosphorylation may permit more information about the agents and conditions affects on sperm function. In the present study, to examine the effect of ECs on human sperm function, human spermatozoa were incubated with a group of ECs represent a widespread chemicals in the environment bisphenol A (BPA, 100 μM), nonylphenol (NP, 10 μg/ml), 2,3,7,8-Tetrachlorodibenzo- pdioxin (TCDD, 2.5 μg/ml), genistein (Gen, 100 μM), and the following pesticides, dibromochloropropane (DBCP, 10 μg/ml), atrazine (Atraz, 500 μM), and diazinone (Diaz, 500 μM) for 6 hr at 37℃ in 5% CO2. Then, western blot analysis was carried out using extracted sperm proteins. Antiphosphorylation antibody (pY20) was used to determine sperm tyrosine phosphorylation after EDs treatment. The pY20 antibody labeled three common bands of approximately 90, 110, and 150 KDa. There were no significant differences between negative and positive control groups in regard to the tyrosine phosphorylated proteins except at the band with molecular weight 110 KDa. However, except Diaz treatment group, the other treatment groups showed decreasing (TCDD, Gen, NP, BPA, and DBCP) or increasing (Atraz) in the tyrosine phosphorylated proteins at least in one band from the three common bands studied. Therefore, it sug-gests that ECs effectively alters human sperm function and this effect may detect via their effect on tyrosine phosphorylation pattern.

It is well known that the imbalance between epithelial cell growth and inhibitor factors may cause human epithelial cancer. Over-expression of the epidermal growth factor receptor(EGFR) has been implicated in the development of oral squamous cell carcinoma. ZD1839 inhibits selectively the EGFR tyrosine kinase activity and is clinically used for cancer patients. However the mechanisms by which it exerts its anti-tumor activity remains unclear. This study attempted to determine the mechanisms underlying the effects of ZD1839 on the cellular level and to characterize the effects of ZD1839 with regard to human oral squamous cell carcinoma(OSCC) cell growth. The YD-10B and YD-38 cell lines established from OSCC in the department of Oral Pathology, Yonsei University College of Dentistry and ZD1839(Iressa) were used for this study. The inhibition of cell proliferation induced by ZD1839 was reversible and the lowest dose of ZD1839 that produced statistically significant growth inhibition in YD cell lines were 0.1 μM. The delay in cell cycle progression was induced by 0.1 μM of ZD1839 treatment after 24 hr. This reduction in cell proliferation and cell cycle delay were associated with up-regulation of the cyclin dependent kinase inhibitor(CDKI), P21CIP1/WAF1 and P27KIP1. Reduced expression of cyclin D1 was also observed after treatment with ZD 1839 to YD-38 cells but not to YD-38. The present results suggest that the antiproliferative effects of ZD1839, in vitro was associated with degradation of cyclin D1, which may be used as a possible indicator of a high cell sensitivity to ZD1839.

Brevibactericum속 균주로 부터 N.T.G. 처리하여 1차로 140개의 변이주를 선별하였다. 이들 균주로 부터 2차 확인후 50균주를 선택 생성량을 보았다. 그 중 가장 생성량이 많은 균주 APT-104(phe-) 균주를 다시 N.T.G. 처리하여 PFP 내성 균주 13균주를 분리하여 그 중 가장 생성량 높은 균주를 다시 N.T.G. 처리하여 PFP 농도가 높은 곳에서 내성이 강한 균주를 5균주 선택 하였다. 이상 선택한 균주의 L-tyrosine 생성량을 비교 검토한 결과 PFP-106 균주에서 가장 높은 생성을 보였다. (50mg/l) 따라서 이 균주의 배지조건을 검토하였다. 그 결과 탄소원에서의 영향은 Sucrose 나 glucose 첨가시 76mg/l, 50mg/l 로서 효과적이었으며 그 농도는 10% 농도가 가장 효과적 이었다. 질소원에서는 (NH_4)_2SO_4첨가시가 50mg/l 로 높았고 다른 질소원은 오히려 낮은 생성을 보였다. 그 농도는 3%가 적당하였다. 아미노산의 영향은 glutamic acid와 L-tryptophane 생성에서 각각 106mg/l, 108mg/l로서 가장 효과적이었다. 또한 L-phenylalanine 의 농도는 100mg/l 첨가시 L-tyrosine 생성량이 50mg/l로서 가장 효과적이었다.