This paper presents a cellular automaton model without step back to simulate the pedestrian counter flow in a channel. The consideration of the surrounding environment when people make judgments on moving directions is added to a random walker model also without step back. Two types of walkers: the right walkers going to the right and the left walkers going to the left are taken into account. The characteristics of counterflow are clarified. Influences of the different interaction radius values and system sizes on movement are studied. Phase transition from free moving to jamming is observed with the increase of entrance density. It is found that the critical entrance density pc at the transition point does not depend on the system size when the interaction radius value is large. Simulation results are represented as a comparison with the random walker model.

Streptomyces coelicolor A3(2) does not have a canonical cell division cycle during most of its complex life cycle, yet it contains a gene (ftsK SC ) encoding a protein similar to FtsK, which couples the completion of cell division and chromosome segregation in unicellular bacteria such as Escherichia coli. Here, we show that various constructed ftsK SC mutants all grew apparently normally and sporulated but upon restreaking gave rise to many aberrant colonies and to high frequencies of chloramphenicol-sensitive mutants, a phenotype previously associated with large terminal deletions from the linear chromosome. Indeed, most of the aberrant colonies had lost large fragments near one or both chromosomal termini, as if chromosome ends had failed to reach their prespore destination before the closure of sporulation septa. A constructed FtsK SC -enhanced green fluorescent protein fusion protein was particularly abundant in aerial hyphae, forming distinctive complexes before localizing to each sporulation septum, suggesting a role for FtsK SC in chromosome segregation during sporulation. Use of a fluorescent reporter showed that when ftsK SC was deleted, several spore compartments in most spore chains failed to express the late-sporulation-specific sigma factor gene sigF, even though they contained chromosomal DNA. This suggested that sigF expression is autonomously activated in each spore compartment in response to completion of chromosome transfer, which would be a previously unknown checkpoint for late-sporulation-specific gene expression. These results provide new insight into the genetic instability prevalent among streptomycetes, including those used in the industrial production of antibiotics.Bacteria of the gram-positive genus Streptomyces are of great interest for their mycelial growth and complex development, as well as being major producers of antibiotics. On solid media, Streptomyces spores germinate and grow into a vegetative mycelium from which aerial hyphae emerge, eventually developing into chains of unigenomic spores. Vegetative hyphae have only sparse septation without actual cell separation; each hyphal compartment contains several unsegregated copies of the chromosome (16). In contrast, during sporulation of aerial hyphae, regularly spaced septa form synchronously in long multigenomic compartments, each receiving one chromosome, and cell separation eventually takes place. Unlike the situation in dividing bacteria such as Escherichia coli, initiation of sporulation septation in Streptomyces often occurs over unsegregated chromosomes, which do not separate until very late in septation (31, 39). This raises the question of how Streptomyces clears chromosomal DNA from sites of septal closure to ensure faithful segregation of the replicated linear chromosomes to progeny spores, avoiding guillotining by septal closure. Completion of chromosome transfer to daughter cells in E. coli is carried out by a septum-located multifunctional protein, FtsK, which is deposited at the FtsZ ring and couples closure of t...

Extracellular matrix protein-1 (ECM1) promotes tumorigenesis in multiple organs but the mechanisms associated to ECM1 isoform subtypes have yet to be clarified. We report in this study that the secretory ECM1a isoform induces tumorigenesis through the GPR motif binding to integrin αXβ2 and the activation of AKT/FAK/Rho/cytoskeleton signaling. The ATP binding cassette subfamily G member 1 (ABCG1) transduces the ECM1a-integrin αXβ2 interactive signaling to facilitate the phosphorylation of AKT/FAK/Rho/cytoskeletal molecules and to confer cancer cell cisplatin resistance through up-regulation of the CD326-mediated cell stemness. On the contrary, the non-secretory ECM1b isoform binds myosin and blocks its phosphorylation, impairing cytoskeleton-mediated signaling and tumorigenesis. Moreover, ECM1a induces the expression of the heterogeneous nuclear ribonucleoprotein L like (hnRNPLL) protein to favor the alternative mRNA splicing generating ECM1a. ECM1a, αXβ2, ABCG1 and hnRNPLL higher expression associates with poor survival, while ECM1b higher expression associates with good survival. These results highlight ECM1a, integrin αXβ2, hnRNPLL and ABCG1 as potential targets for treating cancers associated with ECM1-activated signaling.

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