Anaplasma phagocytophilum is the etiologic agent of human granulocytic anaplasmosis. MSP2(P44), the bacterium's major surface protein, is encoded by a paralogous gene family and has been implicated in a variety of pathobiological processes, including antigenic variation, host adaptation, adhesion, porin activity, and structural integrity. The consensus among several studies performed at the DNA and RNA levels is that a heterogeneous mix of a limited number of msp2(p44) transcripts is expressed by A. phagocytophilum during in vitro cultivation. Such analyses have yet to be extended to the protein level. In this study, we used proteomic and molecular approaches to determine that MSP2(P44)-18 is the predominant if not the only paralog expressed and is modified into multiple 42-to 44-kDa isoforms by A. phagocytophilum strain HGE1 during infection of HL-60 cells. The msp2(p44) expression profile was homogeneous for msp2(p44)-18. Thus, MSP2 (P44)-18 may have a fitness advantage in HL-60 cell culture in the absence of selective immune pressure. Several novel 22-to 27-kDa MSP2 isoforms lacking most of the N-terminal conserved region were also identified. A. phagocytophilum MSP2(P44) orthologs expressed by other pathogens in the family Anaplasmataceae are glycosylated. Gas chromatography revealed that recombinant MSP2(P44)-18 is modified by glucose, galactose, xylose, mannose, and trace amounts of other glycosyl residues. These data are the first to confirm differential modification of any A. phagocytophilum MSP2(P44) paralog and the first to provide evidence for expression of truncated versions of such proteins.

The application of rock magnetism methods to investigating the variations of magnetic minerals in the sediments is an important approach to the reestablishment of paleoclimate evolution. Thus we performed fine magnetic measurements on the loess-paleosol sequence (from L15 upwards to S5, in which L is short for Loess, S is short for Paleosol, the same hereinafter) of Yushan stratigraphic section, which is on the southeastern margin of Chinese Loess Plateau, in Lantian County of China's Shaanxi Province, and the thickness of which is ca. 40 m. Our study shows that the primary magnetic carriers of loess and paleosol in this section are magnetite, maghemite, hematite and goethite. Thermomagnetic analyses on the samples of representative horizons show that the higher pedogenesis degree of the sediments, the smaller variations of magnetization there will be before and after heating, probably related to the pedogenic alteration of loess sediments. Analyses of several magnetic parameters show a significant discrepancy between the paleoclimatic conditions recorded in the strata from the loess unit L15 upward to the paleosol unit S5 in the study area and those recorded in the relative strata of other sections on the Chinese Loess Plateau, and those recorded in marine sediments, indicating the great impact of regional geological background. Similarly, the rapid and intensive change recorded in the segment from L15 to S9-1, and the significant difference between the paleoclimate evolutions of the two periods before and after the change (from L15 to S9-1, and from L9 to the base of S6) indicate the strong alteration of magnetic carriers in the study area as a result of the alternations of summer and winter monsoons in East Asia.Loess Plateau, loess, paleosol, magnetic mineral, paleoclimate change Citation:Wu Y, Zhu Z Y, Rao Z G, et al. Mid-Late Quaternary loess-paleosol sequence in Lantian's Yushan, China: An environmental magnetism approach and its paleoclimatic significance.

x expression coincided with both differential expression and glycosylation of A. phagocytophilum Msp2(P44). This reinforces the hypothesis that this bacterium is able to generate a large variety of surfaceexposed molecules that could provide great antigenic diversity and result in multiple binding properties.

In order to enhance variation induced by the tissue culture process and to obtain agronomically desirable mutants, friable embryogenic tissue cultures of maize (Zea mays L.) inbred line B73 were x‐ray irradiated with 11 doses [0–8.4 kilorads (kR)]. Reductions in callus growth rate and embryogenic callus formation occurred with increasing x‐ray doses 20 d and 3 months (90 d) after irradiation. Callus irradiated with 0.8 kR showed a significant increase in growth rate and a 20% increase in embryogenic callus 9 months (270 d) after irradiation. A total of 230 R0 plants were regenerated for evaluation. Pollen fertility and seed set of R0 plants decreased with increasing x‐ray dosage. Days to anthesis and plant height of R0 plants varied among x‐ray treatments but were generally reduced with higher dosages. The number of chromosomal aberrations increased with x‐ray dosage. The R1 seeds taken from R0 plants were also grown and tested for mutant segregation. Plants regenerated from irradiated calli had a two‐ to 10‐fold increase in mutations over plants regenerated from unirradiated control callus. Germination frequency of seeds from R0 plants decreased with increasing x‐ray dosage. Although chlorophyll mutants were most frequently observed, a number of vigorous plants with earlier anthesis date were also recovered.

Plantain zonate leaf spot, caused by Pestalotiopsis menezesiana, was found for the first time in China on a plantation at Jinling town of Nanning city, Guangxi province in 2005. The fungus was isolated and pathogenicity confirmed. The fungus was sensitive to prochloraz, iprodione, thiabendazole and triazole fungicides in vitro. Pathogenicity tests showed that the pathogen could infect banana cultivars (Musa AAA) as well as plantain (Musa AAB) under artificial inoculation conditions. However, the disease could only be found on the leaves of plantain in the fields. This is the first record of Pestalotiopsis menezesiana on plantain in China.