Studies have explored the influence of DNA damage in assisted reproductive technology (ART), but the outcome remains controversial. To determine whether sperm DNA fragmentation index (DFI) has any effect on ART outcomes, we collected detailed data regarding 1,333 IVF cycles performed at our centre, and the data of our retrospective cohort study were extracted for this meta‐analysis. We searched PubMed, Web of Science, EMBASE and Google Scholar and performed a systemic review and meta‐analysis. Primary meta‐analysis of 10 studies comprising 1,785 couples showed that live birth rate was no significantly different between low‐DFI group and high‐DFI group (p > 0.05). Secondary meta‐analysis of 25 studies comprising 3,992 couples showed a higher miscarriage rate in high‐DFI group than in low‐DFI group (RR=1.57 [1.18, 2.09], p < 0.01). Meta‐analysis of eight studies comprising 17,879 embryos revealed a lower good‐quality embryo rate (RR=0.65 [0.62, 0.68], p < 0.01). Meta‐analysis of 23 studies comprising 6,771 cycles showed that the high‐DFI group had a lower clinical pregnancy rate than low‐DFI group (RR=0.85 [0.75, 0.96], p < 0.01). Heterogeneity of included studies weakened our conclusions. Our study showed that DFI has adverse effects on ART outcome. More well‐designed studies exploring the association between DFI and ART outcome are desired.

Many phytopathogenic fungi use infection structures (IFSs, i.e., appressoria and infection cushions) to penetrate host cuticles. However, the conserved mechanisms that mediate initiation of IFS formation in divergent pathogens upon sensing the presence of host plants remain obscure. Here, we demonstrate that a conserved septin gene SEP4 plays crucial roles in this process. Disruption of SEP4 in the plant grey mould fungus Botrytis cinerea completely blocked IFS formation and abolished the virulence of ΔBcsep4 mutants on unwounded hosts. During IFS formation, mutants lacking SEP4 could produce reactive oxygen species (ROS) normally. Inhibition of ROS production in strains harbouring the SEP4 gene resulted in disordered assembly of Sep4 and the subsequent failure to form infection cushions, suggesting that proper Sep4 assembly regulated by ROS is required for initiation of IFS formation and infection. Moreover, loss of SEP4 severely impaired mutant conidiation, melanin and chitin accumulation in hyphal tips and lesion expansion on wounded hosts, but significantly promoted germ tube elongation and sclerotium production. SEP4-mediated fungal pathogenic development, including IFS formation, was validated in the hemibiotroph Magnaporthe oryzae. Our findings indicate that Sep4 plays pleiotropic roles in B. cinerea development and specifically facilities host infection by mediating initiation of IFS formation in divergent plant fungal pathogens in response to ROS signaling.

Flagella and cilia are structurally polarized organelles whose lengths are precisely defined, and alterations in length are related to several human disorders [1, 2]. Intraflagellar transport (IFT) and protein signaling molecules are implicated in specifying flagellar/ciliary length [3–6], but evidence has been lacking for a flagellum/cilium length sensor that could participate in active length control or establishment of structural polarity. Previously, we showed that the phosphorylation state of the aurora-like protein kinase CALK in Chlamydomonas is a marker of the absence of flagella. Here, we show that CALK phosphorylation state also is a marker for flagellar length. CALK is phosphorylated in cells without flagella, and during flagellar assembly it becomes desphosphorylated. Dephosphorylation is not simply a consequence of initiation of flagellar assembly or of time after experimentally-induced flagellar loss, but requires flagellar assembly to a threshold length. Analysis of cells with flagella of varying lengths shows that the threshold length for CALK dephosphorylation is ~6 µm (half-length). Studies with short and long flagellar mutants indicate that cells detect absolute rather than relative flagellar length. Our results demonstrate that cells possess a mechanism for translating flagellar length into a posttranslational modification of a known flagellar regulatory protein.

Recently, Yao et al. demonstrated the creation of coherent emissions in nitrogen gas with two-color (800 nm + 400 nm) ultrafast laser pulses [New J. Phys. 15, 023046 (2013)]. Based on this two-color scheme, here we report on systematic investigation of temporal characteristics of the coherent emission at)) by experimentally examining its evolution with the increase of the plasma channel induced by the intense 800 nm femtosecond laser pulses at a nitrogen gas pressure of ∼25 mbar. We reveal unexpected temporal profiles of the coherent emissions, which show significant superradiance signatures owing to the quantum coherence via cooperation of an ensemble of excited N 2 + molecules. Our findings shed more light on the mechanisms behind the laser-like emissions induced by strong-field ionization of molecules.