褐飞虱翊型分化遗传规律的研究

以褐飞虱Nilaparvata lugens (Stal)长翅型(macroptery,简称M)、短翅型(brachyptery,简称B)的遗传纯系为实验材料,进行亲本、稻株生育期、虫口密度三因子交互实验。结果表明：(1)在环境条件(指稻株生育期、虫口密度等)一致时,B♀×B♂、B♀×M♂、M♀×B♂、M♀×M♂四种亲本组合的F1代短翅型成虫百分率分别为：98%、92%、64%、29%,各亲本组合间差异极显著;(2)亲本相同时,将F1代褐飞虱初孵若虫多头词养(多于l0头/株)在黄熟期稻株上,其长翅型雌、雄成虫百分数均高于灌浆期稻株上;(3)单头饲养实验中发现,不论亲本组合、稻株生育期如何,雌虫绝大多数分化为短翅型,而雄虫则几乎全为长翅型。这表明褐飞虱的翅型分化遗传由一个受多种因子影响的调控体系决定,且调控作用与性别有关。     

The majority of long non-stop reading frames on the antisense strand can be explained by biased codon usage

In recent studies it has been suggested that long reading frames on the antisense strand of open reading frames (ORFs) are more frequent than expected. The vertebrate DNA database was searched for long (greater than 900 bp) antisense non-stop reading frames (aNRFs) that overlap known coding regions. The sequences obtained were predominantly positioned in DNA with a high usage of Gor C in the third codon position of the sense ORF. The major class of sequences revealed by the search was that of the heat-shock protein 70 kDa (Hsp70) family. A long Hsp70 aNRF was found in many Hsp70 sequences and occurred in species as diverse as fish, flies, fungi and bacteria. The role of codon usage bias was analysed both in the specific case of the Hsp70 genes and in a general species-wide context. The data obtained showed that even the very long aNRFs present in the Hsp70 family could be explained by codon usage bias on the sense strand. Codon usage bias is determined by GC content at the third codon position of the sense ORF and, in some species, by a high expression level of the gene in question. Such an explanation for the occurrence of long aNRFs cannot exclude that some aNRFs are transcribed and translated.     

Oviduct binding ability of porcine spermatozoa develops in the epididymis and can be advanced by incubation with caudal fluid

The sperm reservoir is formed when spermatozoa bind to the epithelium of the uterotubal junction and caudal isthmus of the oviduct. It is an important mechanism that helps synchronize the meeting of gametes by regulating untimely capacitation and polyspermic fertilization. This study investigated the influence of epididymal maturation and caudal fluid on the ability of spermatozoa to bind to oviduct epithelium using a model porcine oviduct explant assay. Spermatozoa from the rete testis, middle caput (E2-E3), middle corpus (E6), and cauda (E8) of Large White or Large White × Landrace boars aged 10 to 14 months were diluted in modified Androhep solution and incubated with porcine oviduct explants. Results reported in this study support our hypothesis that testicular spermatozoa need to pass through the regions of the epididymis to acquire the ability to bind to the oviduct. There was a sequential increase in the number of spermatozoa that bound to oviduct explants from the rete testis to caudal epididymis. Binding of caudal spermatozoa to isthmic explants was the highest (15.0 ± 1.2 spermatozoa per 1.25 mm², mean ± standard error of the mean; P ≤ 0.05) and lowest by spermatozoa from the rete testis (2.0 ± 0.3 per 1.25 mm²), and higher to isthmus from sows compared to gilts (35.8 ± 6.7 per 1.25 mm² vs. 14.8 ± 3.0 per 1.25 mm²; P ≤ 0.05). Binding of ejaculated spermatozoa to porcine isthmus was higher than that for caudal spermatozoa (26.3 ± 1.4 per 1.25 mm² vs. 15.0 ± 0.8 per 1.25 mm²; P ≤ 0.05) and higher to porcine than to bovine isthmus (26.3 ± 2.3 per 1.25 mm² vs. 18.8 ± 1.9 per 1.25 mm²; P ≤ 0.05). Incubation of spermatozoa from the caput and corpus in caudal fluid increased the ability of spermatozoa to bind to the oviduct epithelium (P ≤ 0.05). In conclusion, the capacity of testicular spermatozoa to bind to the oviduct epithelium increases during their maturation in the epididymis and can be advanced by components of the caudal fluid.     

Potato Tuber Growth and Yield Under Red and Blue LEDs in Plant Factories

Journal of Plant Growth Regulation - To investigate the effects of red and blue light on potato growth and yield, potato plantlets were transplanted under white (W), red (R), blue (B), and...     

The influence of nitrogen on the development and accumulation of protein bodies in the developing endosperm of wheat caryopses

The aim of the present work was to reveal the histological changes of protein bodies (PBs) in the developing wheat endosperm under nitrogen (N) treatment. For this purpose, the development and accumulation of PBs in the dorsal and ventral regions of wheat endosperm affected by N application at booting stage were investigated using light microscopy and Image-Pro Plus 6.0 software. The endosperm without N treatment contained many smaller PBs that were scattered in endosperm cells in an unordered pattern, whereas the endosperm with N treatment contained many larger PBs or aggregations that were concentrated in a certain region of endosperm cells. The amount and relative areas of PBs in wheat varieties cvs. Xumai 30 and Yangmai 13 were significantly increased by N application. However, the cultivars differed with the degree of response to N being cv. Xumai 30 > cv. Yangmai 13. These differences also varied with position in the endosperm in the order ventral > dorsal region. The initiation of PBs occurred 3 days earlier in N-treated endosperm than the control.     

Immunomodulatory activities of a new pentapeptide (Bursopentin) from the chicken bursa of Fabricius

The bursa of Fabricius (BF) is a central immune organ in birds, and some peptides from chicken BF have demonstrated important immune functions. Here, a new 626.27 Da pentapeptide, Bursopentin (BP5, Cys-Lys-Arg-Val-Tyr) was isolated and purified by reverse-phase high-performance liquid chromatography. In this study, we examined the effects of BP5 on antigen-specific immune response in BALB/c mice sensitized with inactivated avian influenza virus (AIV) [A/Duck/Jiangsu/NJ08/05 (AIV H9N2 subtype)]. The results suggested that BP5 enhanced anti-hemagglutinin antibody (IgG, the isotypes IgG1 and IgG2a) production, induced both of Th1- (IL-2 and IFN-γ) and Th2-type (IL-4 and -10) cytokines, increased proliferations of splenic lymphocyte subsets CD4+ T cells (CD3+CD4+), CD8+ T cells (CD3+CD8+) and B cells, and enhanced cytotoxic T-lymphocyte activity of the activated splenocytes against NIH3T3 cells. The effects of BP5 on the proliferation of isolated T- and/or B-cell populations of BALB/c mice were assessed, and the data suggested that BP5 promoted spleen lymphocyte proliferation by activating B cells directly and T cells indirectly. Further analysis revealed that B-lymphocyte proliferation induced by BP5 is mediated by reactive oxygen species generated from thiol auto-oxidation of BP5. Furthermore, our data indicated that protein kinase C, mitogen-activated protein kinase, and nuclear factor kappa B are involved in the signal transductions during the BP5-induced B lymphocyte proliferation. This study indicates that BP5 could be a potential immunomodulator for future immuno-pharmacological use.