Project description:High-throughput sequencing of endogenous small RNAs from the moss Physcomitrella patens. This dataset encompasses microRNAs and other small RNAs of ~20-24 nucleotides expressed in the moss P. patens. SAMPLES UPDATED JULY 9, 2007 TO INCLUDE DATA ON SEQUENCED SMALL RNAS THAT DO NOT MATCH THE P. PATENS GENOME Keywords: High throughput small RNA sequencing
Project description:To investigate the effects of dcl3,dcl4,mDCL,rdr2,rdr6,nrpd1b, and nrpd1c mutations upon small RNAs in Physcomitrella patens , small RNA-seq was performed.
Project description:To obtain the gene expression profiles of the moss Physcomitrella patens ABA insensitive mutant AR7, we performed microarray analysis of wildtype plant and AR7 using a custom Physcomitrella oligonucleotide microarray, which carries probes for 33,942 gene models of Physcomitrella genome version 1.1. on a 4 x 44 K Agilent platform.
Project description:The meiotic spindle in oocytes is formed without centrosomes. How a bipolar spindle is assembled and maintained around chromosomes in oocytes remains to be established. Multiple kinases are known to regulate the meiotic spindle, but how they execute their function is poorly understood. We found that the phospho-docking protein 14-3-3ε, together with the other isoform ζ, stabilises spindle bipolarity in Drosophila oocytes. A critical 14-3-3 target is the minus-end directed motor Ncd (human HSET; kinesin-14) which has well documented roles in stabilising a bipolar spindle in oocytes. Phospho-docking by 14-3-3 inhibits the microtubule binding activity of the non-motor Ncd tail. Further phosphorylation by Aurora B kinase can release Ncd from this inhibitory effect of 14-3-3. As Aurora B localises to chromosomes and spindles, 14-3-3 facilitates specific association of Ncd with spindle microtubules by preventing Ncd from binding to non-spindle microtubules in oocytes. Therefore, 14-3-3 translates a spatial cue provided by Aurora B to target Ncd selectively to the spindle within the large volume of oocytes.
Project description:To investigate the disruption effect of Group A PP2C on global gene expression in Physcomitrella patens, we performed microarray analysis of wildtype plant and PpABI1 disruptants using a custom Physcomitrella oligonucleotide microarray, which carries probes for 33,942 gene models of Physcomitrella genome version 1.1. on a 4 x 44 K Agilent platform.
Project description:Transcription profiling of Physcomitrella patens Reute strain gametophore, mature sporophyte and spore stage. These samples are part of an large-scale expression data set for the model moss Physcomitrella patens.
Project description:The mitotic kinesin-like Protein 2 (MKLP2, KIF20A) is essential for the proper execution of cytokinesis and required to ‘passage’ the chromosomal passenger complex (CPC) from the chromosomes in (pro)metaphase to the spindle midzone and equatorial cortex in anaphase. Together with MKLP1 (KIF23) and MPP1 (KIF20B), MKLP2 forms the kinesin-6 subfamily of motor proteins. Whilst MKLP1 and MPP1 are both plus-end directed processive motors, the typical structure of the MKLP2 motor domain along with the extended neck-linker region, suggested that MKLP2 might not be able to function as a transport motor but is more likely to act as a microtubule bundler. This notion contradicts the prevailing hypothesis that MKLP2 can transport the CPC in anaphase, but appears to be in line with in vitro and in cellulo studies showing that recombinant MKLP2 efficiently bundles microtubules, and that knock-down of MKLP2, disturbs the organization of the anaphase spindle midzone. Using TIRF microscopy and purified fluorescent proteins, we here demonstrate that MKLP2 is a plus-end directed processive motor that can transport the CPC along microtubules in vitro. Live imaging of MKLP2::GFP and INCENP::GFP in early anaphase cells revealed that a fraction of both MKLP2 and INCENP displays directed movements towards the (equatorial) cortex. In line, inhibition of MKLP2 ATPase activity at the start of anaphase disturbed the localization of MKLP2 and CPC at the equatorial cortex. Our data suggest that MKLP2 is a processive microtubule-based motor that transports itself and the CPC to the equatorial cortex.
Project description:Kinesins are a superfamily of molecular motors that undertake ATP-dependent microtubule-based movement or regulate microtubule dynamics. Plasmodium species, which cause malaria and kill hundreds of thousands annually, encode ~9 kinesins in their genomes. Of these, two – kinesin-8B and kinesin-8X - are canonically classified as kinesin-8s, which in other eukaryotes typically modulate microtubule dynamics. Unexpectedly, Plasmodium kinesin-8B is required for development of the flagellated male gamete in the mosquito host, and its absence completely blocks parasite transmission. To understand the molecular basis of kinesin-8B’s essential role, we characterised the in vitro properties of the kinesin-8B motor domains from P. berghei and P. falciparum. Both motors drive plus-end directed ATP-dependent microtubule gliding, but also catalyse ATP-dependent microtubule depolymerisation. We determined the microtubule-bound structures of these motors using cryo-electron microscopy. P. berghei and P. falciparum kinesin-8B exhibit a very similar mode of microtubule interaction, in which Plasmodium-distinct sequences at the microtubule-kinesin interface influence motor function. Intriguingly, however, P. berghei kinesin-8B exhibits a non-canonical structural response to ATP analogue binding such that neck linker docking is not induced. Nevertheless, the neck linker region is absolutely required for motility and depolymerisation activities of these motors. Taken together, these data suggest that the mechanochemistry of Plasmodium kinesin-8Bs has been functionally tuned to efficiently contribute to flagella formation.
Project description:The intracellular function of myosin motors requires a number of adaptor molecules, which control cargo attachment, but also fine-tune motor activity in time and space. These motor-adaptor-cargo interactions are often weak, transient or highly regulated. To overcome these problems we use a proximity labelling-based proteomics strategy (BioID) to map the interactome of the unique minus end-directed actin motor MYO6. Our analysis identified several distinct MYO6-adaptor modules including two complexes containing RHO GEFs which we screened using further BioID baits (LRCH3, DOCK7, GIPC1 and ARHGEF12). These complexes emphasise the multifunctionality of MYO6 provides the first in vivo interactome of a myosin motor protein, highlighting the power of this approach in uncovering dynamic and functionally diverse myosin motor complexes.