OBJECTIVETo explore the patterns of Cx43 and Pax3 protein expressions in the small intestinal muscular layers of human embryo during early development.

METHODSImmunohistochemistry with SABC method was employed to examine the expression of Cx43 and Pax3 proteins in the muscular layers of the small intestine in early human embryos in the second to fourth months of gestation.

RESULTSIn the second month of gestation, the muscle layer of the small intestine was negative for Cx43 and Pax3 protein expressions. In the third month, Cx43 and Pax3 expressions were negative in the inner circular muscle layer, but some positive cells were found in the longitudinal muscle layer and the myenteric plexus. In the fourth month, positive expression of Cx43 and Pax3 proteins were seen in the entire muscle layer.

CONCLUSIONCx43 and Pax3 proteins are closely related to the growth and development of the cells and tissues in the small intestinal muscle layer in human embryos.

Connexin 43 ; biosynthesis ; Embryo, Mammalian ; metabolism ; Humans ; Immunohistochemistry ; Intestine, Small ; embryology ; metabolism ; Muscle, Smooth ; embryology ; metabolism ; PAX3 Transcription Factor ; Paired Box Transcription Factors ; biosynthesis

OBJECTIVETo study the expression of carbonic anhydrase IX (CAIX), PAX2 and PAX8 in different types of renal epithelial tumor and their association with clinicopathologic characteristics.

METHODSImmunohistochemical study by EnVision method was performed in order to assess the expression of CAIX, PAX2 and PAX8 in 155 cases of renal cell carcinoma and 4 cases of metastatic clear cell renal cell carcinoma (CCRCC). Ninety-six cases of non-neoplastic renal parenchymal tissue adjacent to CCRCC, 8 cases of clear cell hepatocellular carcinoma and 2 cases of clear cell hidradenoma were used as controls.

RESULTSCAIX was commonly expressed in CCRCC (94.0%, 63/67), of which 77.8% (49/63) showed strong positivity. CAIX was focally positive in papillary renal cell carcinoma, collecting duct carcinoma and urothelial carcinoma of renal pelvis. It was negative in chromophobe renal cell carcinoma, oncocytoma and adjacent non-neoplastic renal tissue. CAIX was also strongly expressed in the 4 cases of metastatic CCRCC. Focal expression of CAIX was demonstrated in the 8 cases of clear cell hepatocellular carcinoma and 2 cases of clear cell hidradenoma. The expression of CAIX in CCRCC did not correlate with tumor grading, clinical staging and presence of distal metastasis. On the other hand, PAX2 showed positive expression in different types of renal epithelial tumor, clear cell hepatocellular carcinoma and clear cell hidradenoma in various degrees. In contrast, PAX8 was commonly expressed in all types of renal epithelial tumor, with the exception of urothelial carcinoma of renal pelvis. PAX8 was not expressed in clear cell hepatocellular carcinoma and clear cell hidradenoma. Regarding diagnosis of CCRCC, CAIX demonstrated high sensitivity and specificity. PAX2 showed high specificity but low sensitivity. PAX8 was sensitive and specific in the diagnosis of renal epithelial tumor.

CONCLUSIONSCAIX is a useful immunohistochemical marker with high specificity and sensitivity in distinguishing CCRCC from other types of renal epithelial tumor and clear cell tumors of non-renal origin. PAX2 is a marker with high sensitivity and low specificity for diagnosis of renal epithelial tumors. PAX8 is typically expressed in renal epithelial tumors. The combined detection of CAIX, PAX2 and PAX8 is useful in the diagnosis and differential diagnosis of renal epithelial tumors.

Adenoma, Oxyphilic ; metabolism ; pathology ; Antigens, Neoplasm ; metabolism ; Carbonic Anhydrase IX ; Carbonic Anhydrases ; metabolism ; Carcinoma, Renal Cell ; metabolism ; pathology ; Diagnosis, Differential ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; Male ; PAX2 Transcription Factor ; metabolism ; PAX8 Transcription Factor ; Paired Box Transcription Factors ; metabolism

OBJECTIVETo investigate the distribution pattern of the expressions neuronal nitric oxide synthase (nNOS), Pax3 and connexin 43 (Cx43) proteins in the early developing posterior horn of embryonic and fetal human spinal cord.

METHODSImmunohistochemistry was used to detect the expressions of nNOS, Pax3 and Cx43 proteins in the posterior horn of the spinal cord during the second, third and fourth month of human embryonic and fetal development.

RESULTSIn the second to fourth month of gestation, the expressions of nNOS and Pax3 proteins increased gradually from weak expression to strong expression in the posterior horn of the spinal cord. In the second to third month of development, Cx43 protein expression was negative in the posterior horn of the spinal cord, but positive in the myelin sheath. In the fourth month, positive Cx43 expression was detected in some of the cells in the posterior horn of the spinal cord.

CONCLUSIONnNOS, Pax3 and Cx43 proteins are closely related to the growth and development of the spinal cord in human embryos and fetuses.

Connexin 43 ; metabolism ; Embryo, Mammalian ; cytology ; metabolism ; Female ; Fetus ; cytology ; metabolism ; Gene Expression Regulation, Developmental ; Humans ; Nitric Oxide Synthase Type I ; metabolism ; PAX3 Transcription Factor ; Paired Box Transcription Factors ; metabolism ; Posterior Horn Cells ; metabolism ; Pregnancy

BACKGROUNDPax-6 gene plays an important role in the process of eye development. This study was to determine the role of pax-6 in the axial myopia produced by hyperopic optical defocus and form deprivation in infant monkeys.

METHODSAmong seven normal infant rhesus monkeys (aged 1 to 1.5 months), five wore -3.00 D spectacle lenses over their right eyes and zero-powered lenses over their left eyes. Monocular form deprivation was produced by eyelid fusion in two monkeys. Ten weeks later, the monkeys were sacrificed by an overdose of barbiturates and their eyes were removed immediately. A 5 mm x 5 mm button of retina and sclera was taken from the posterior poles along with a 4-mm optic nerve. RNA was isolated separately from each of these three types of tissues. After that, reverse transcription polymerase chain reaction (RT-PCR) was used for determining gene expression in the retina, sclera and optic nerve. Semi-quantitative analyses were performed on the PCR products.

RESULTSAs expected, the optically induced hyperopic defocus and the form deprivation produced myopic growth. For the lens-treatment monkeys, pax-6 gene expression in the retinas of the defocused eyes was significantly higher than in the retinas of the left eyes (t = 5.703, P = 0.005). However, there were no analogous significant differences between pax-6 expression in the scleras or the optic nerves. For the two form-deprived monkeys, there were no obvious differences in pax-6 gene expression in the retinas or the optic nerves.

CONCLUSIONThe result that the expression of pax-6 was enhanced by hyperopic defocus in the infant monkey retina suggests that pax-6 may be involved in vision-dependent eye growth and emmetropization.

Animals ; Eye Proteins ; Gene Expression Regulation ; Homeodomain Proteins ; genetics ; Macaca mulatta ; Myopia ; metabolism ; Optic Nerve ; metabolism ; PAX6 Transcription Factor ; Paired Box Transcription Factors ; Repressor Proteins ; Retina ; metabolism ; pathology ; Reverse Transcriptase Polymerase Chain Reaction ; Sclera ; metabolism

Pax6 and its Drosophila homolog Eyeless (Ey) play essential roles during eye development. Ey/Pax6 contains two distinct DNA binding domains, a Paired domain (PD) and a Homeodomain (HD). While Ey/Pax6 PD is required for the expression of key regulators of retinal development, relatively little is known about the HD-dependent Ey function. In this study, we used the UAS/GAL4 system to determine the functions of different Ey domains on cell growth and on retinal development. We showed that Ey can promote cell growth, which requires the HD but not the PD. In contrast, the ability of Ey to activate Ato expression and induce ectopic eye formation requires the PD but not the HD. Interestingly, deletion of the HD enhanced Ey-dependent ectopic eye induction while overexpression of the HD only Ey forms antagonizes ectopic eye induction. These studies revealed a novel function of Ey HD on cell growth and a novel antagonistic effect of Ey HD on Ey PD-dependent eye induction. We further show the third helix of the Ey HD can directly interact with the RED subdomain in Ey PD and that deletion of the HD increased the binding of Ey PD to its target. These results suggest that the direct interaction between the HD and the PD potentially mediates their antagonistic effects. Since different Ey splicing forms are expressed in overlapping regions during normal development, we speculate that the expression ratios of the different Ey splice forms potentially contribute to the regulation of growth and differentiation of these tissues.
Animals ; Animals, Genetically Modified ; metabolism ; Binding Sites ; Cell Differentiation ; Cell Proliferation ; DNA-Binding Proteins ; metabolism ; Drosophila ; metabolism ; Drosophila Proteins ; antagonists & inhibitors ; metabolism ; Enhancer Elements, Genetic ; Eye Proteins ; antagonists & inhibitors ; metabolism ; Homeodomain Proteins ; antagonists & inhibitors ; metabolism ; PAX6 Transcription Factor ; Paired Box Transcription Factors ; antagonists & inhibitors ; metabolism ; Protein Structure, Tertiary ; Repressor Proteins ; antagonists & inhibitors ; metabolism ; Retina ; cytology ; metabolism ; Wings, Animal ; growth & development

Humans ; Hypoxia-Inducible Factor-Proline Dioxygenases ; metabolism ; Ki-67 Antigen ; metabolism ; MicroRNAs ; metabolism ; Neoplasm Grading ; Neoplasm Staging ; Neprilysin ; metabolism ; Neuroendocrine Tumors ; classification ; diagnosis ; metabolism ; pathology ; surgery ; PAX8 Transcription Factor ; Paired Box Transcription Factors ; metabolism ; Pancreatic Neoplasms ; classification ; diagnosis ; metabolism ; pathology ; surgery ; Prognosis ; Tumor Suppressor Proteins ; metabolism

Mouse embryonic stem (mES) cells are capable of undergoing chondrogenesis in vitro. To enhance this process, the human SOX9 (hSOX9) cDNA was delivered into mES cells and the clones overexpressing hSOX9 (denoted as mES-hSOX9 cells) were verified by Western blot analysis. The transcripts of collagen IIA (a juvenile form), aggrecan and Pax1 were expressed in mES-hSOX9 cells grown on feeder layers, suggesting the immediate effect of exogenous SOX9 on chondrogenesis. However, SOX9 overexpression did not affect the cell cycle distribution in undifferentiated mES cells. Upon differentiation, collagen IIB (an adult form) was detected in day 3 immature embryoid bodies. In addition, the overexpression of exogenous SOX9 significantly induced transcriptional activity driven by SOX9 binding site. Taken together, we for the first time demonstrated that constitutive overexpression of exogenous SOX9 in undifferentiated mES cells might have dual potentials to induce both chondrogenic commitment and growth capacity in the undifferentiated status.
Animals ; Cell Differentiation/genetics ; Cell Line ; *Chondrogenesis ; Collagen Type II/genetics ; Embryo/*cytology ; Enhancer Elements (Genetics)/genetics ; Extracellular Matrix Proteins/genetics ; Genetic Markers/genetics ; High Mobility Group Proteins/genetics/*metabolism ; Humans ; Lectins, C-Type/genetics ; Mice ; Paired Box Transcription Factors/genetics ; Proteoglycans/genetics ; Research Support, Non-U.S. Gov't ; Stem Cells/*metabolism/physiology ; Trans-Activation (Genetics) ; Transcription Factors/genetics/*metabolism

To investigate the function of ALK3 gene, the gene regulation and the signaling pathway related to ventricular septum defect during heart development. The model mice with ALK3 gene knock-out via alpha-MHC-Cre/lox P system were bred. The mRNA expression level of control group was compared with that of experiment group and ALK3 downstream genes were screened using PCR-select cDNA subtraction microarray. The mRNA of control group was extracted from E11.5 normal mouse hearts, and that of experiment group, from E11.5 hearts of mice with alpha-MHC Cre(+/-) ALK3(F/+) genotype. It was found that the mice with ALK3 gene knock-out produced heart defects involving the interventricular septum. The platelet-activating factors acetylhydrolase and the transcription factor Pax-8 and so on, were down-regulated. However, the Protein Tyrosine Kinase (PTK) of Focal Adhesion Kinase (FAK) subfamily and beta subtype protein 14-3-3 were up-regulated in the alpha-MHC Cre(+/-) ALK3(F/-) mice. These data provide support that ALK3 gene played an important role during heart development. The platelet-activating factors acetylhydrolase and Pax-8 genes could be important ALK3 downstream genes in the BMP signaling pathway during interventricular septum development. PTK and beta subtype protein 14-3-3 might be regulatory factors in this pathway.
1-Alkyl-2-acetylglycerophosphocholine Esterase ; genetics ; metabolism ; 14-3-3 Proteins ; genetics ; metabolism ; Animals ; Bone Morphogenetic Protein Receptors, Type I ; genetics ; metabolism ; Genotype ; Heart Septal Defects, Ventricular ; genetics ; Mice ; Mice, Knockout ; Oligonucleotide Array Sequence Analysis ; PAX8 Transcription Factor ; Paired Box Transcription Factors ; genetics ; metabolism ; Protein-Tyrosine Kinases ; genetics ; metabolism ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; genetics ; physiology

Members of the inhibitors of differentiation (Id) family of helix-loop-helix (HLH) proteins are known to play important roles in the proliferation and differentiation of many cell types. Thyroid-stimulating hormone (TSH) regulates proliferation and differentiation by activating TSH receptor (TSHR) in thyrocytes. In this study, we found that Id2, one of the Id family proteins, is a major target for regulation by TSH in FRTL-5 thyroid cells. TSH rapidly increases the Id2 mRNA level in FRTL-5 thyroid cells but the Id2 protein showed biphasic regulatory patterns, being transiently reduced and subsequently induced by TSH treatment. Transient reduction of Id2 protein was noted within 2 hr of TSH treatment and was mediated by proteasomal degradation. Moreover, reduced Id2 expression correlated with the activity of the phosphatidylinositol 3 kinase pathway, which is activated by TSH. Although TSH increases the activity of the Id2 promoter, TSH-induced activation of this promoter was independent of c-Myc. Id2 did not alter TTF-1- and Pax-8-mediated effects on the regulation of the Tg promoter. Thus, in summary, we found that TSH regulates Id2 expression, but that Id2 does not alter the expression of thyroid-specific genes, such as Tg, in FRTL-5 thyroid cells.
1-Phosphatidylinositol 3-Kinase/metabolism ; Animals ; Cattle ; Cell Differentiation ; Cell Proliferation ; *Gene Expression Regulation ; Inhibitor of Differentiation Protein 2/metabolism ; Insulin/metabolism ; Paired Box Transcription Factors/metabolism ; Promoter Regions, Genetic ; Proto-Oncogene Proteins c-myc/metabolism ; Rats ; Thyroglobulin/metabolism ; Thyroid Gland/*cytology ; Thyrotropin/*metabolism

OBJECTIVEConventional deletion of ALK3, also termed as bone morphogenetic protein (BMP) receptor IA, in mice might result in early embryonic lethality. To investigate the function of ALK3 in cardiac development, the cardiac-specific deletion of ALK3 in mice was made by Dr. Schneider, using Cre recombinase driven by the alpha-MHC promoter that Dr. Fukushipe worked out. Such specific deletion of ALK3 caused death in mid-gestation with defects in the trabeculae, interventricular septum, and endocardial cushion. Since ALK3 is not a cardiac-specific gene, it is extremely important to identify ALK3 downstream genes.

METHODSAlpha-MHC Cre+/-, ALK3 F/- and alpha-MHC Cre+/-, ALK3 F/+ embryos were obtained after 20 alpha-MHC Cre+/-, ALK3 +/- mice and 20 ALK3 F/F mice were mating. The ALK3 downstream genes were screened using microarray made in Germany that could identify 25000 genes in mouse. Two populations of mRNA, one derived from the embryonic heart (11.5 days) of alpha-MHC Cre+/-, ALK3 F/- mice, and the other derived from the alpha-MHC Cre+/-, ALK3 F/+ mice, were compared. Cardiac-specific ALK3 downstream genes were identified using real time quantitative RT-PCR and in situ hybridization.

RESULTSThe expression of 12 genes, such as Pax-8 and Hox-3.5 were down-regulated in alpha-MHC Cre+/-, ALK3 F/- mouse heart. The expression of 16 genes including Ras-related protein Rab-5b and EPS-8 protein was up-regulated in the group of alpha-MHC Cre+/-, ALK3 F/-. It was found that the Box protein Pax-8 gene was down-regulated by 7.1 fold (P < 0.001) in the alpha-MHC Cre+/-, ALK3 F/- mice by real time quantitative RT-PCR. It was also revealed that the Box protein Pax-8 gene was expressed stronger in alpha-MHC Cre+/-, ALK3 F/+ than alpha-MHC Cre+/-, ALK3 F/- E11.5 days mouse heart by means of in situ hybridization.

CONCLUSIONThe Box protein Pax-8 gene is an important and cardiac-specific ALK3 downstream gene in the BMP signaling pathway during inter-ventricular septum development.

Animals ; Bone Morphogenetic Protein Receptors ; DNA-Binding Proteins ; genetics ; Down-Regulation ; Female ; Heart ; embryology ; Male ; Mice ; Mice, Inbred C57BL ; Mice, Knockout ; Myocardium ; metabolism ; pathology ; Nuclear Proteins ; Oligonucleotide Array Sequence Analysis ; PAX8 Transcription Factor ; Paired Box Transcription Factors ; Receptors, Growth Factor ; genetics ; physiology ; Reverse Transcriptase Polymerase Chain Reaction ; Trans-Activators ; genetics