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Bing Qi

Publications and source records attributed to Bing Qi.

24 records · Page 2Linked to original sources
PubMed2003

Pro-apoptotic ASY/Nogo-B protein associates with ASYIP.

We have previously shown that ectopic expression of the ASY/Nogo-B gene induced apoptosis in various cancer cell lines. Nogo-A, a splice variant of the ASY, has been reported to have an inhibitory effect on neuronal regeneration in the central nervous system. To investigate the mechanism of ASY-induced apoptosis or inhibition of neuronal regeneration, we cloned a cDNA for the ASY-interacting protein from the human cDNA library using the yeast two-hybrid method, and obtained a cDNA we designated as ASYIP. The ASYIP protein contains two hydrophobic regions and a double lysine endoplasmic reticulum (ER) retrieval motif at its C-terminus, which was shown to be identical to RTN3, a reticulon family protein of unknown function. We showed that ASY and ASYIP proteins formed a complex also in human cells. Mutational analysis indicated that both of the hydrophobic regions of the ASYIP protein were required for the association. By immunofluorescence analysis, the ASYIP protein was shown to be co-localized with ASY in the ER. Characterization of the ASYIP gene may be very useful in clarifying the mechanism of ASY-induced apoptosis or Nogo-involved inhibition of neuronal regeneration in the central nervous system.

Amino Acid Sequence↗
PubMed2003

In vivo Doppler optical coherence tomography of mucocutaneous telangiectases in hereditary hemorrhagic telangiectasia.

BACKGROUND: Hereditary hemorrhagic telangiectasia is characterized by mucocutaneous telangiectases and visceral arteriovenous malformations. Knowledge is limited concerning the development hemodynamics of mucocutaneous telangiectases. Doppler optical coherence tomography can demonstrate microvascular blood flow at flow rates as low as 20 microm/second, which is up to approximately 100 times more sensitive than Doppler US. The aims of this study were to collect in vivo Doppler optical coherence tomography images of mucocutaneous telangiectases and normal surrounding mucosa and skin, and to gain experience for an in vivo GI endoscopic study. It was hypothesized that visibly normal areas may have occult telangiectases and that mucocutaneous telangiectases that have bled may have a higher rate of blood flow than mucocutaneous telangiectases with no history of bleeding. METHODS: Twelve patients with hereditary hemorrhagic telangiectasia and mucocutaneous telangiectases were studied. Two to 3 visible mucocutaneous telangiectases on the digits, lips, and tongue were imaged with Doppler optical coherence tomography, along with visually normal surrounding areas at each site. The Doppler optical coherence tomography images were obtained in 0.5 second by using 1310 nm light. RESULTS: A total of 67 mucocutaneous telangiectases from the 12 patients were imaged (38 digit, 16 lip, 13 tongue). Blood flow was demonstrated within every mucocutaneous telangiectasis imaged. Doppler optical coherence tomography did not identify any abnormal vasculature within visually normal areas. Mucocutaneous telangiectases with a history of bleeding (n = 18) were situated closer to the surface, compared with mucocutaneous telangiectases with no bleeding history (n = 49), but there was no difference in the Doppler flow appearance. CONCLUSIONS: Visually normal areas in patients with hereditary hemorrhagic telangiectasia did not appear to have abnormal vasculature. Mucocutaneous telangiectases with a history of bleeding were more superficial but were otherwise similar to mucocutaneous telangiectases with no bleeding history.

Adult↗
PubMed2002

Generation of multiple mRNA transcripts from the novel human apoptosis-inducing gene hap by alternative polyadenylation utilization and the translational activation function of 3' untranslated region.

hap, a novel human apoptosis-inducing gene, was identified to have two major mRNA species of 1.8 and 2.7 kb in length by Northern blot analysis of poly(A)(+) RNA from multiple human tissues. The two hap transcripts derive from the alternative polyadenylation site selection: an AATAAA signal at position 1528-1533 nt for the 1.8 kb mRNA, and an AATAAA signal at position 2375-2380 nt for the 2.7 kb mRNA. The 3'-UTR spanning the region between the second and the third polyadenylation site of 2.7 kb hap was demonstrated to exert a translational activation function for hap itself and the reporter gene chloramphenicol acetyltransferase (CAT) expression by approximately threefold, despite no differences observed in the steady-state level of relative cytoplasmic mRNA. Comparing the mRNA stability of two hap transcripts indicated that the longer mRNA was not more stable than the short one. Taken together, all these data provide evidence that the hap 3'-UTR containing within the second and the third polyadenylation signal can regulate gene translation rather than transcription and mRNA stability.

3' Untranslated Regions↗
PubMed2000

Transcription and Translation of Sendai Virus Hemagglutinin-neuraminidase (HN) in Mammalian Cells.

Sendai virus hemagglutinin-neuraminidase was expressed in COS-7 cells. LLCMK(2) cells were transfected with expression plasmids harboring HN, namely pJH3, pJH4 or pJH7, and were passaged conti-nuously under the presence of hygromycin or puromycin to get antibiotic-resistant clones, which had HN gene integrated into genomes. S1 nuclease assay indicated that large quantity of HN mRNA was transcribed but indirect-immunofluorescence and immunoprecipitation demonstrated that there was little HN protein expressed on cell surface and inside cells, in contrast with the Sendai virus persistent-infected LLCMK(2) cells that expressed largely HN protein. Therefore, not every transcription resulted in translation. It also suggests that some virus factors may positively regulate transcription and translation of HN mRNA.

Journal Article↗
PubMedDate not supplied

Analysis of gene expression in rabbit nuclear transfer embryos: Use of single-embryo mRNA differential display.

Lack of or abnormal expression of developmentally important genes is believed to hamper early development of the nuclear transfer (NT) embryo. To identify stage-specific genes in rabbit NT embryo development, mRNA differential display was used to compare the mRNA content of rabbit NT embryos at different developmental stages, from Metaphase II oocytes to 8-16-cell stage embryos. Thirty-four zygotic transcripts, which abruptly appeared at the 8-16-cell stage in rabbit NT embryos, were isolated; 11 of these were potential novel genes with no matches in the current databases. Of the remaining 23, 12 were matched with established sequence tags with functions uncharacterized and the other 11 were homologous to those in the European Molecular Biology Laboratory (EMBL) and GenBank databases. The differential expression of eight of the 34 amplicons were confirmed by reverse Northern blotting, and four positive clones were validated. Previous studies and present data indicated that these three genes were probably related to preimplantation rabbit embryo development.

Animals↗