Clock1a affects mesoderm development and primitive hematopoiesis by regulating Nodal-Smad3 signaling in the zebrafish embryo.

Circadian clock and Smad2/3/4-mediated Nodal signaling regulate multiple physiological and pathological processes. However, it remains unknown whether Clock directly cross-talks with Nodal signaling and how this would regulate embryonic development. Here we show that Clock1a coordinated mesoderm development and primitive hematopoiesis in zebrafish embryos by directly up-regulating Nodal-Smad3 signaling. We found that Clock1a is expressed both maternally and zygotically throughout early zebrafish development. We also noted that Clock1a alterations produce embryonic defects with shortened body length, lack of the ventral tail fin, or partial defect of the eyes. Clock1a regulates the expression of the mesodermal markers ntl, gsc, and eve1 and of the hematopoietic markers scl, lmo2, and fli1a Biochemical analyses revealed that Clock1a stimulates Nodal signaling by increasing expression of Smad2/3/4. Mechanistically, Clock1a activates the smad3a promoter via its E-box1 element (CAGATG). Taken together, these findings provide mechanistic insight into the role of Clock1a in the regulation of mesoderm development and primitive hematopoiesis via modulation of Nodal-Smad3 signaling and indicate that Smad3a is directly controlled by the circadian clock in zebrafish.

[Identification and expression analysis of Macaca mulatta piwil4 gene].

To investigate the structure and expression pattern of rhesus monkey PIWIL4 protein, homologous comparison and reverse transcription PCR (RT-PCR) were carried out to identify rhesus monkey piwil4. The expression of piwil4 mRNA was tested in rhesus monkey heart, brain, colon, epididymis and testis, and the result showed that piwil4 mRNA was expressed in these rhesus monkey tissues. Bioinformatic analysis suggested that the rhesus PIWIL4 protein shared 97% identity in amino acids and the same domains such as PAZ and Piwi with the human PIWIL4 (HIWI2) protein. The immunohistochemical result indicated that PIWIL4 proteins had the same localization in adult testes of the two species, but the distribution of these proteins was altered dynamically at different developmental stages in rhesus monkey testes. PIWIL4 protein was expressed in the nucleus of convoluted seminiferous tubules in infant monkey testes, whereas it was expressed in the cytoplasm of adult monkey testes. The results suggest that piwil4 gene play a similar role in rhesus and human, and different localizations of PIWIL4 protein in infant monkey and adult monkey testes suggest that it functions differently at different developmental stages.

[Initial study on zili functions to the development of the germ layers during zebrafish early embryogenesis].

OBJECTIVE: To study the role for piwil2 gene (zili) in the development of the ectoderm, mesoderm and endoderm during early embryogenesis of zebrafish. METHODS: zili morpholino antisense oligonucleotide and 5 mis-pair control morpholino were used in this study. zili was cloned into expression vector. zili mRNA was synthesized in vitro. The antisense RNA probes of gsc, evel and sox17 were synthesized. zili-MO, zili-cMO and zili mRNA was microinjected into one-cell embryos, respectively. Whole-mount in situ hybridization was used to monitor the expressions of marker genes. RESULTS: Microinjection of zili-MO, which knocked down the expression of zili, downregulated the expression of the ectodermal and mesodermal marker gene gsc, promoting the expression of the ectodermal marker gene evel and resulting in the decrease of endodermal cell expressed sox17. The overexpression of zili, promoting the expression of gsc, inhibiting the expression of eve1 and resulting in the decrease of endodermal cell expressed sox17 were observed after microinjection of zili-mRNA. CONCLUSION: zili might have some effect on the formation of the ectoderm, mesoderm and endoderm during early embryogenesis and might be important for normal embryonic development.

CLOCK and BMAL1 stabilize and activate RHOA to promote F-actin formation in cancer cells.

Circadian genes control most of the physiological functions in cancer cells, including cell proliferation, migration, and invasion. The CLOCK and BMAL1 complex plays a central role in circadian rhythms. Previous studies have shown that circadian genes may act as oncogenes or tumor-suppressor genes. In addition, F-actin, regulated by RHOA, has been shown to participate in tumor progression. However, the roles of the CLOCK and BMAL1 genes in the regulation of tumor progression via the RHOA-ROCK-CFL pathway remain largely unclear. Here we first indicate that the rearrangement of F-actin is regulated by CLOCK and BMAL1. We found that CLOCK and BMAL1 can upregulate RHOA expression by inhibiting CUL3-mediated ubiquitination and activate RHOA by reducing the interaction between RHOA and RhoGDI. Consequently, CLOCK and BMAL1 control the expression of the components of the RHOA-ROCK-CFL pathway, which alters the dynamics of F-actin/G-actin turnover and promotes cancer cell proliferation, migration, and invasion. In conclusion, our research proposes a novel insight into the role of CLOCK and BMAL1 in tumor cells.

[Gene mutation analysis of coagulation factor VIII from a female patient with hemophilia A].

Hemophilia A affects male, whereas females are carriers and generally spared from this disease. However, we here reported a 65-year-old female with Hemophilia A while screening the gene mutation of coagulation factor VIII. The female went to hospital because of tripping to lead her right chest to be injured with subcutaneous hematoma. She had historically a hemorrhagic diathesis. The physical examination discovered her hip limited to bend and move, but no discrepancy length between her two legs. The initial laboratory tests showed that the activated partial thromboplastin time (APTT) was 61. 3 seconds (20-40 seconds), and the APTT corrected by mixing with normal plasma was 41.3 s, but the levels of PT, FIB and TT were normal. The plain radiographs revealed the hip joints to suffer from the acetabular dysplasia and osteoarthritis. The level of FVIII:C was 2%, F IX:C 200%, vWF:Ag 120%, vWF:Rcof 100%, vWF:CBA 128%, and the F VIII binding assay to vWF was normal. The primers for exon 14 of F VIII gene were designed according to the NM - 000132 gene sequence. DNA was abstracted from the patient blood. PCR were carried out and the DNA sequence was followed. A new mutation of 4111A-->C was discovered, which caused the amino acid sequence changed (T 1314 P). The mutation of T 1314 P may be the cause of this female patient to get the hemophilia A. This mutation was a novel one which has never been reported before.

Post-delivery mycobacterium tuberculosis infection misdiagnosed as systemic lupus erythematosus.

Tuberculosis is a common infectious mycobacterial disease having a wide range of clinical and serological manifestations that are similar to rheumatic disease. Differential diagnosis is a crucial aspect in any rheumatic disease as many other infectious diseases portray clinical similarities and autoantibody positivity. Our case report illustrates of a young woman just after the delivery of a child presented an unusual case of extrapulmonary tuberculosis infection initially misdiagnosed as systemic lupus erythematosus (SLE).

Toll-like receptor 4 detected in exocrine pancreas and the change of expression in cerulein-induced pancreatitis.

OBJECTIVES: To detect Toll-like receptor 4 (TLR4) expression and distribution in rat pancreas and the change of TLR4 expression in cerulein-induced pancreatitis (CIP). METHODS: Acute pancreatitis was induced by subcutaneous injections of cerulein at a total dose of 20 microg/kg. Immunohistochemistry (IHC) was used to detect and localize TLR4 in rat pancreas, and real-time reverse transcription-polymerase chain reaction (RT-PCR) was used to quantitatively determine the expression of TLR4 mRNA in CIP. RESULTS: IHC showed the presence of TLR4 in rat pancreas, and its distribution was specifically localized to pancreatic ductal epithelium, vascular endothelium, and islet. No TLR4 staining was detected in exocrine acinar cells. Real-time RT-PCR results revealed low-level TLR4 mRNA expression in the rat pancreas, and the change of TLR4 in CIP only developed within the first 4 hours, which is a rapid up-regulation process that peaks at the first hour. TLR4 mRNA was sustained at baseline level from 4 to 24 hours. CONCLUSIONS: TLR4 protein was expressed in pancreas and localized to epithelial (pancreatic duct) or endothelial (vessels) tissues; TLR4 responded favorably to the inflammatory process, and the change of expression was characterized as a rapid up-regulation in the early stage of CIP.