Momordica anti-HIV protein MAP30 abrogates the Epstein-Barr virus nuclear antigen 1 dependent functions in host cells.

Originally extracted from Momordica charantia seeds, the antiviral and anti-tumor activities of Momordica anti-HIV protein MAP30 have become well known. Although MAP30 has been reported to possess antiviral activity against several human viruses, the current understanding of the MAP30-mediated antiviral response is mainly derived from the previous research work on anti-HIV herbal medicines; the mechanistic insight of its effects on other viruses remains largely unknown. In this study, we showed that both ectopically expressed and purified recombinant MAP30 (rMAP30) impeded Epstein-Barr virus Nuclear Antigen 1 (EBNA1)-mediated transcription from the viral latent replication origin. Mechanistically, in vivo and in vitro studies revealed that MAP30 caused EBNA1 to dissociate from the cognate binding sites, which disrupted downstream EBNA1-dependent viral epigenome accumulation and cell maintenance of Epstein-Barr virus (EBV)-associated neoplastic cells. Finally, mutational analysis indicated that the N-terminal ricin A homologous domain shared by ricin-like proteins was implicated in the anti-EBV response. Our study provides evidence to support that MAP30 has a unique property to combat EBV latent infection, suggesting a potential to develop this herbal protein to be an alternative medicine for EBV associated diseases.

Paralysis periodica paramyotonica caused by SCN4A Arg1448Cys mutation.

Paralysis periodica paramyotonica is an overlapping disease that shares the features of paramyotonia characteristic of paramyotonia congenita (PC) and periodic paralysis characteristic of hyperkalemic periodic paralysis. We report the case of a 23-year-old man with paralysis periodica paramyotonica. His father and a younger brother also exhibited a similar phenotype. A SCN4A Arg1448Cys mutation was detected in this family. The affected family members exhibited marked shifts in compound muscle action potential amplitudes on exercise test, and muscle weakness could be induced by potassium loading and cold exposure. This case demonstrates that SCN4A Arg1448Cys can produce paralysis periodica paramyotonica. Other genetic or environmental factors may modulate the manifestation of SCN4A Arg1448Cys mutation.

X-ray multiple-wave coherent interaction in a quasi-two-dimensional material NbSe2-2H.

The first observation of the X-ray multiple-wave interaction in an incommensurate charge-density-wave (CDW) modulated structure at low temperatures is reported for an example of a quasi-two-dimensional material, NbSe(2)-2H. Via the coherent interaction between the X-ray waves propagating in the CDW-modulated structure and the host structure, the phase-dependent intensity variations of a CDW reflection were detected. In accord with a centrosymmetric structure, the phases of the structure-factor triplets of two CDW reflections and a Bragg reflection of the host structure were determined to be either 0 or 180 degrees, and not to vary with temperature. Relative phase differences of the two CDW reflections are also deduced.