The blood-brain barrier (BBB) keeps poisons and infections out of the brain.  Some viruses can pass through this barrier and replicate in the central nervous system (CNS).  Velogenic Newcastle disease virus (VNDV) is a neurotropic virus that causes avian nonsuppurative encephalitis.  VNDV often develops into a chronic infection that seriously affects poultry health in partially immune birds.  The routes by which the virus enters the chicken brain are poorly understood.  In this study, we discovered that VNDV increased BBB permeability in vivo and in vitro by breaking the tight junction protein zona occludens-1 (ZO-1) continuity of chicken brain microvascular endothelial cells (chBMECs).  By investigating the susceptibility of chBMECs to NDV infection, we found that VNDV but not lentogenic NDV was detected in the basolateral compartment in transwell assays after apical infection, suggesting that efficient replication and transcellular transport of the virus across the BBB in vitro.  Furthermore, viral replication and BBB permeability were reduced during the early stage of infection by using the dynamin inhibitor dynasore.  Our data demonstrate that VNDV invades the chicken brain by infecting and damaging the tight junction of chBMECs directly to increase BBB permeability.  VNDV could infect chBMECs via endocytosis.  As a result, our findings provide compelling evidence for VNDV entrance into the brain via the BBB, paving the way for the development of medications for NDV prevention and therapy.

Sugarcane has recently attracted increasing attention for its potential as a source of sugar and bioethanol, so increasing its yield is essential to ensure the sugar security and bioenergy production.  Intergeneric hybridization is a highly efficient method to produce new genetic variants of crop plants, particularly those species with high ploidy such as sugarcane (Saccharum spp.).  Tripidium arundinaceum exhibits many desirable agronomic traits, and has been widely studied to produce hybrids with improved stress tolerance and other characteristics in sugarcane breeding.  However, the genetic relationship between T. arundinaceum and Saccharum species, and the individual T. arundinaceum chromosomal compositions in sugarcane hybrids are still elusive.  Here we used whole-genome single-nucleotide polymorphisms (SNPs) to ascertain the phylogenetic relationships between these species and found that T. arundinaceum is more closely related to Saccharum than Sorghum, in contrast to the previous narrow genetic analyses using chloroplast DNA.  Additionally, oligonucleotide (oligo)-based chromosome-specific painting derived from Saccharum officinarum was able to distinctly identify the chromosomes of T. arundinaceum.  We developed the oligo-genomic in situ hybridization (GISH) system for the first time, to unveil the novel chromosome translocations and the transmission of individual T. arundinaceum chromosomes in sugarcane progeny.  Notably, we discovered that the chromosomal transmission of T. arundinaceum exhibited several different inheritance modes, including n, 2n, and over 2n in the BC₁ progenies.  Such inheritance patterns may have resulted from first division restitution (FDR) or FDR+nondisjunction of a chromosome with the sister chromatids in the second meiosis division/second division restitution (FDR+NSC/SDR) model during meiosis.  These results will be of substantial benefit for the further selection of T. arundinaceum chromosomes for sugarcane genetic improvement.