Moths use multimodal sensory information to adopt adaptive resting orientations

Camouflage conceals animals from predators and depends on the interplay between the morphology and behaviour of animals. Behavioural elements of animals, such as the choice of a resting spot or posture, are important for effective camouflage, as well as the animals’ cryptic appearance. To date, the type of sensory input that mediates resting site choice remains poorly understood. Previously, we showed that bark‐like moths perceive and rely on bark structure to seek out cryptic resting positions and body orientations on tree trunks. In the present study, we investigated the sensory organs through which moths perceive the structure of bark when positioning their bodies in adaptive resting orientations. We amputated (or blocked) each one of the hypothetical sensory organs in moths (antennae, forelegs, wings, and eyes) and tested whether they were still able to perceive bark structure properly and adopt adaptive resting orientations. We found that visual information or stimulation is crucial for adaptively orienting their bodies when resting and tactile information from wings may play an additional role. The present study reveals multimodal information use by moths to achieve visual camouflage and highlights the sensory mechanism that is responsible for the adaptive behaviour of cryptic insects. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 111 , 900–904.     

Differential Effects of Tachykinins Injected Intranigrally on Striatal Dopamine Metabolism

The effects of intranigral injection of kassinin, eledoisin, and substance P on striatal dopamine (DA) and 3,4-dihydroxyphenylacetic acid (DOPAC) contents as well as circling behavior were studied in rats. Kassinin and eledoisin produced a marked dose-dependent increase of DOPAC concentrations in the ipsilateral striatum, as well as in the number of contralateral circlings. Substance P produced a similar but weaker effect. At the larger dose (5 nmol), the three tachykinins also induced an increase of DA concentrations in the ipsilateral striatum. The rank order of activity was kassinin greater than eledoisin greater than substance P. These results suggest that tachykinins stimulated the nigro-striatal dopaminergic system by accelerating the dopamine metabolism in striatum.     

DNA polymerases in midgestation mouse embryo, trophoblast, and decidua

The DNA polymerases of midgestation mouse embryo, trophoblast, and decidua have been examined. A low molecular weight, nuclear. DNA-dependent polymerase (D-DNA polymerase) and a higher molecular weight cytoplasmic enzyme were found in all three cell types. A DNA polymerase which utilized the poly(A) strand of oligo(dT) · poly(A) as template (R-DNA polymerase) was also found in the three cell types. This enzyme was present both in the nucleus and the cytoplasm. All enzyme levels were highest in the rapidly dividing embryonic cells, substantially lower in the DNA replicating but nondividing trophoblast cells, and lowest in the nonreplicating, nondividing decidual cells. Our observations are consistent with the idea that the nuclear and cytoplasmic D-DNA polymerases are under coordinate control. The relationship of these enzymes to DNA synthesis in vivo is discussed.     

ULK2 Ser 1027 Phosphorylation by PKA Regulates Its Nuclear Localization Occurring through Karyopherin Beta 2 Recognition of a PY-NLS Motif

Uncoordinated 51-like kinase 2 (ULK2), a member of the serine/threonine kinase family, plays an essential role in the regulation of autophagy in mammalian cells. Given the role of autophagy in normal cellular homeostasis and in multiple diseases, improved mechanistic insight into this process may result in the development of novel therapeutic approaches. Here, we present evidence that ULK2 associates with karyopherin beta 2 (Kapβ2) for its transportation into the nucleus. We identify a potential PY-NLS motif (⁷⁷⁴gpgfgssppGaeaapslRyvPY⁷⁹⁵) in the S/P space domain of ULK2, which is similar to the consensus PY-NLS motif (R/K/H)X _2–5PY. Using a pull-down approach, we observe that ULK2 interacts physically with Kapβ2 both in vitro and in vivo. Confocal microscopy confirmed the co-localization of ULK2 and Kapβ2. Localization of ULK2 to the nuclear region was disrupted by mutations in the putative Kapβ2-binding motif (P794A). Furthermore, in transient transfection assays, the presence of the Kapβ2 binding site mutant (the cytoplasmic localization form) was associated with a substantial increase in autophagy activity (but a decrease in the in vitro serine-phosphorylation) compared with the wild type ULK2. Mutational analysis showed that the phosphorylation on the Ser1027 residue of ULK2 by Protein Kinase A (PKA) is the regulatory point for its functional dissociation from Atg13 and FIP 200, nuclear localization, and autophagy. Taken together, our observations indicate that Kapβ2 interacts with ULK2 through ULK2’s putative PY-NLS motif, and facilitates transport from the cytoplasm to the nucleus, depending on its Ser1027 residue phosphorylation by PKA, thereby reducing autophagic activity.     

Kinase Signaling in the Spindle Checkpoint

The spindle checkpoint is a cell cycle surveillance system that ensures the fidelity of chromosome segregation. In mitosis, it elicits the “wait anaphase” signal to inhibit the anaphase-promoting complex or cyclosome until all chromosomes achieve bipolar microtubule attachment and align at the metaphase plate. Because a single kinetochore unattached to microtubules activates the checkpoint, the wait anaphase signal is thought to be generated by this kinetochore and is then amplified and distributed throughout the cell to inhibit the anaphase-promoting complex/cyclosome. Several spindle checkpoint kinases participate in the generation and amplification of this signal. Recent studies have begun to reveal the activation mechanisms of these checkpoint kinases. Increasing evidence also indicates that the checkpoint kinases not only help to generate the wait anaphase signal but also actively correct kinetochore-microtubule attachment defects.     

Protein modification by phosphorylation during the process of nuclear membrane dissolution in puromycin-treated mouse oocytes.

The present study was undertaken to elucidate the mechanism of nuclear membrane dissolution (NMD) in puromycin-treated mouse oocytes. Treatment of germinal vesicle breakdown (GVBD) oocytes with puromycin (50 micrograms/ml) induced chromosome decondensation with formation of a polar body; these are designated nuclear membrane (NM) oocytes. After withdrawal of puromycin, NM oocytes underwent NMD (approximately 70%) during a 12-h culture period. Either dibutyryl cyclic AMP (dbcAMP, 25-100 micrograms/ml) or isobutylmethylxanthine (IBMX, 0.1-1.0 mM) inhibited the process of NMD in a dose-dependent manner, suggesting the involvement of cAMP in the process of NMD. To determine which protein(s) participated in the transition from interphase to metaphase II during NMD, NM oocytes were labeled with [35S]methionine, and one- and two-dimensional gel electrophoresis were performed. Although the synthesis of stage-specific proteins during NMD was not found, two specific proteins of Mr 27,000 and 46,000, which were synthesized at interphase following removal of puromycin, were modified during NMD. Phosphatase treatment and 32PO4-labeling experiments indicated that phosphorylation was responsible for these modifications, which were inhibited by either dbcAMP or IBMX. Therefore, it appears that phosphorylation of specific proteins may play an important role in the transition from interphase to metaphase II.     

秤锤树属与长果安息香属植物的地理分布及其濒危现状

秤锤树属(SinojackiaHu)和长果安息香属(ChangiostyraxC.T.Chen)是安息香科的少种属,这两属在我国共记录有7个种。本文通过野外调查,分析了中国这两属植物的地理分布、濒危现状及其迁地保护状况。结果表明:秤锤树属植物地理分布较广,但是每个物种的居群数量和居群大小均很小。其中秤锤树(Sinojackiaxylocarpa)和狭果秤锤树(S.rehderiana)已经在其模式标本产地灭绝;棱果秤锤树(S.henryi)在过去的近70年内没有采到过标本,该物种可能存在同物异名现象或已经灭绝;细果秤锤树(S.microcarpa)由于人为破坏严重,居群大小急剧下降;肉果秤锤树(S.sarcocarpa)和怀化秤锤树(S.oblongicarpa)呈零星分布且个体数量很少,处于极濒危状态。另外本次调查发现秤锤树属的一个新的分类群(待鉴定种)。秤锤树属的大多数种和长果安息香属植物的居群更新能力差:虽然结果率较高,但是结籽率较低;坚硬的内果皮阻碍了种子的萌发,这是其居群更新的最大障碍;另外人为破坏对其居群更新的影响也较大。作者建议应该把秤锤树属的所有物种和长果安息香属植物都纳入保护的范围并讨论了这两属植物的保护策略。     

结合基因功能分类体系Gene Ontology筛选聚类特征基因

使用两套基因表达谱数据,按各基因的表达值方差,选择表达变异基因对样本聚类,发现一般使用方差较大的前10％的基因作为特征基因,就可以较好地对疾病样本聚类。对不同的疾病,包含聚类信息的特征基因有不同的分布特点。在此基础上,结合基因功能分类体系(Gene Ontology,GO),进一步筛选聚类的特征基因。通过检验在Gene Ontology中的每个功能类中的表达变异基因是否非随机地聚集,寻找疾病相关功能类,再根据相关功能类中的表达变异基因进行聚类分析。实验结果显示：结合基因功能体系进一步筛选表达变异基因作为聚类特征基因,可以保持或提高聚类准确性,并使得聚类结果具有明确的生物学意义。另外,发现了一些可能和淋巴瘤和白血病相关的基因。     

Mycoparasitism of Rhizoctonia solani by Endophytic Chaetomium spirale ND35: Ultrastructure and Cytochemistry of the Interaction

The interaction between endophytic biocontrol agent Chaetomium spirale ND35 and the soil‐borne plant pathogen Rhizoctonia solani was studied by light microscopy and transmission electron microscopy (TEM), as well as further investigated by gold cytochemistry to assess the potential role of cell wall degrading enzymes (CWDEs) during the mycoparasitic process. Macroscopic observations of fungal growth in dual cultures revealed that pathogen growth inhibition occurred soon after contact with the antagonist, followed by the overgrowth of C. spirale on the colony of R. solani. The coiling of C. spirale around R. solani and intracellular growth of the antagonist in its host occurred frequently. Moreover, in advanced stage of interaction between the antagonist and the pathogen, The growth and development of C. spirale were associated with highly morphological changes of the host fungal cell, characterized by retraction of plasma membrane and cytoplasm disorganization. Further, TEM investigations through localization by gold immunocytochemistry showed that contact between the two fungi was mediated by an amorphous β‐1,3‐glucan‐enriched matrix originating from cell wall of the antagonist C. spirale and sticking to its host surface. At the same time, the hemispherical wall appositions which were intensely labeled by the antibodies of β‐1, 3‐glucan in cell wall of R. solani were induced to form at sites of potential antagonist entry. However, the antagonist was capable of penetrating this barrier, indicating that β‐1,3‐glucanases were produced during the mycoparasitic process. Localization of N‐acetylglucosamine residues (chitin) with the gold‐labelled wheat germ agglutinin (WGA) implicated that chitinases might be involved in the CWD of R. solani in this antagonistic process as well. This report is the first evidence about mechanisms of the interactions between C. spirale and R. solani in ultrastructural and cytochemical aspects.