Primary results of 2-dimensional electrophoresis for protein studies of Gentiana kurroo Royle somatic embryos derived from long-term embryogenic cell suspensions

Two-dimensional gel electrophoresis was used to compare protein expression profiles between various stages of Gentiana kurroo Royle somatic embryos. Seven distinct stages (I–VII) were pointed out and measured from long-term embryogenic cell suspension. Isoelectric focusing was done in the pH intervals 3–10, and the second dimension was carried out with 13% SDS-polyacrylamide gel electrophoresis. Dependent on the stage from about 400 (stage IV) to more than 700 (stage II) protein spots were totally detected. The molecular weight of abundant proteins range from 12 to 70 kDa, however, majority of proteins were located between 20–49 kDa spots on the gels. The highest difference in the number of spots appeared in the case of globular embryo (stage I) and elongated cotyledonary stage (stage VII) with differences being about 130 spots. The relevance of embryogenic cell suspension choice for proteomic analysis as well as expediency of the increasing number of particular embryo stages is discussed

Primary results of 2-dimensional electrophoresis for protein studies of Gentiana kurroo Royle somatic embryos derived from long-term embryogenic cell suspensions

Two-dimensional gel electrophoresis was used to compare protein expression profiles between various stages of Gentiana kurroo Royle somatic embryos. Seven distinct stages (I–VII) were pointed out and measured from long-term embryogenic cell suspension. Isoelectric focusing was done in the pH intervals 3–10, and the second dimension was carried out with 13% SDS-polyacrylamide gel electrophoresis. Dependent on the stage from about 400 (stage IV) to more than 700 (stage II) protein spots were totally detected. The molecular weight of abundant proteins range from 12 to 70 kDa, however, majority of proteins were located between 20–49 kDa spots on the gels. The highest difference in the number of spots appeared in the case of globular embryo (stage I) and elongated cotyledonary stage (stage VII) with differences being about 130 spots. The relevance of embryogenic cell suspension choice for proteomic analysis as well as expediency of the increasing number of particular embryo stages is discussed

Cryopreservation enhances embryogenic capacity of Gentiana cruciata (L.) suspension culture and maintains (epi)genetic uniformity of regenerants

The embryogenic cell suspension culture of Gentiana cruciata, cryopreserved by the encapsulation/dehydration method, survived both short- (48 h) and long-term (1.5 years) cryostorage with more than 80% viability. To assess the influence of cryotreatments on the embryogenic potential, a proembryogenic mass was encapsulated and exposed to the following treatments: (1) osmotic dehydration (OD), (2) OD + air desiccation (AD) and (3) OD + AD + cryostorage (LN). The somatic embryogenesis efficiency increased ten times after osmotic dehydration. The AD and LN cryotreatments did not cause any significant alterations in somatic embryo production. We monitored the (epi)genetic stability of 288 regenerants derived from: non-cryotreated, short-term, and long-term cryostored tissue using metAFLP markers and ten primer combinations. Changes in the sequence and DNA methylation levels were studied by subjecting the DNA to digestion with two pairs of isoschisomer restriction enzymes (KpnI/MseI and Acc65I/MseI). Two new AFLP unique DNA fragments at the DNA sequence level, with no differences at the methylation level, were found between regenerants derived from cryopreserved tissue, compared with the non-cryotreated controls. The Acc65I/MseI methylation levels for the three groups of regenerants were not significantly different. Cluster analysis was capable of identifying a number of sub-clusters. Only one of the sub-clusters comprises almost all regenerants derived from non-cryotreated and short-term cryostored tissue. Plantlets derived from long-term cryostored tissue were grouped into separate clusters. The observed AFLP alterations did not appear to be associated with the use of cryopreservation, but were probably related to the process of in vitro culture

A simple way to overcome the recalcitrance of the water fern Ceratopteris thalictroides (L.) Brongn. to cryopreservation

Ceratopteris thalictroides is a water fern very sensitive to both dehydration and low temperature. This study focuses on the cryopreservation of this species by encapsulation-dehydration technique, in particular on the effects of pre-culture step, alginate bead size and the physical conditions of culture on the cryopreservation efficiency. Encapsulated and non-pre-cultured gametophytes did not survive cooling with liquid nitrogen. When cryopreservation was preceded by a 2-week period of pre-culture, regrowth reached 42.1%. Reduction in the size of the alginate bead, and culture in total darkness resulted in improved gametophyte regrowth capacity (75.5% or 81.7%, respectively). The best results (91.3%) were obtained when all factors tested occurred simultaneously. The gametophytes recovered very quickly and sporophytes were formed within 4 weeks after rewarming. These simple improvements can be used, not only for the cryopreservation of gametophytes in cryptogams but also for some recalcitrant species of seed plants

NA61/SHINE facility at the CERN SPS: beams and detector system

NA61/SHINE (SPS Heavy Ion and Neutrino Experiment) is a multi-purpose experimental facility to study hadron production in hadron-proton, hadron-nucleus and nucleus-nucleus collisions at the CERN Super Proton Synchrotron. It recorded the first physics data with hadron beams in 2009 and with ion beams (secondary 7Be beams) in 2011. NA61/SHINE has greatly profited from the long development of the CERN proton and ion sources and the accelerator chain as well as the H2 beamline of the CERN North Area. The latter has recently been modified to also serve as a fragment separator as needed to produce the Be beams for NA61/SHINE. Numerous components of the NA61/SHINE set-up were inherited from its predecessors, in particular, the last one, the NA49 experiment. Important new detectors and upgrades of the legacy equipment were introduced by the NA61/SHINE Collaboration. This paper describes the state of the NA61/SHINE facility - the beams and the detector system - before the CERN Long Shutdown I, which started in March 2013