Heterochromosomen beiVipera berus L. (Viperidae,Serpentes)

Summary A dimorphic pair of chromosomes was found among the macrochromosomes in mitosis of females ofVipera berus L. It corresponds to a pair of medium-sized chromosomes in the male. The conclusion is drawn that females are heterogametic (ZW-type), males being homogametic (ZZ-type). Similar observations were made inVipera aspis L.,Natrix natrix L., andNatrix maura L.     

Asymmetry and yield inCocos nucifera L.

Zusammenfassung Die Blätter der Kokospalme (Cocos nucifera L.) sind in links- oder rechtsdrehenden Spiralen angeordnet. Zählungen an einem grossen Material indischer und nichtindischer Palmen (3028 bzw. 13842 Bäume) ergab ein geringfügiges Überweigen der linksdrehenden Blattspiralen (52,05% bzw. 52,90%). Der Drehsinn der Spiralen erwies sich, wie Kreuzungsversuche zeigten, als genetisch nicht fixiert. In fünfjährigem Feldversuch (1955–1960) lieferten Palmen mit linksdrehenden Blattspiralen einen signifikant grösseren Ertrag an Kokosnüssen.     

Dystrophic mutation (dy2J) affecting regulation of lactate dehydrogenase (LDH) and pyruvate kinase (PK) in C57BL/6J mice

Summary The genotype difference (dystrophic vs nondystrophic) in the LDH isozymes is observed in kidney. These differences are evident only at birth and at early developmental stages (before the expression of dystrophic symptoms). The tissue specific genotype differences for PK are limited to the thigh muscle (M form) and heart (L form), after the onset of the condition. These differences may reflect the pleiotropic effect of the dy^2J locus during the temporal regulation of these and other enzymes implicated in muscular dystrophy (MD).This research was financed by a Natural Sciences and Engineering Research Council Canada grant to S.M.S.     

Hermidin,a chromogen fromMercurialis perennis L.

Summary Aqueous extracts ofMercurialis perennis L. contain a chromogen (hermidin) shown to be 3,6-dihydroxy-4-methoxy-1-methyl-2-pyridinone (2). The transient blue color formed by atmospheric oxidation of these extracts is due to a radical-anion and the final yellow-brown color is due to dimeric oxidation products.Acknowledgment. I thank Professor R.H. Thomson for his interest.     

Cutaneous respiration in a Selachian (Scyliorhinus caniculus L.)]

Cutaneous oxygen consumption (Mo2) and cutaneous oxygen uptake from the external medium were investigated in an elasmobranch Scyliorhinus caniculus L. In spite of an important Mo2 (2.75 +/- 0.28 nmol.mn-1 cm-2 ; n=6) a positive net flux of oxygen through the skin takes place (2.98 +/- 0.33 nmol. mn-1 .cm-2). The skin of the dogfish in an exchanger for oxygen supplying 10% of oxygen requirements of other organs of the body in these experimental conditions (t = 13 degrees C).     

Seasonal variations in liver metabolism of the green frogRana esculenta (L.)

Summary Rana esculenta (L.) kept under natural conditions show almost constant b.wt in the annual cycle. Liver weight, however, has a distinct peak in October/November which is also evident in the liver index. The liver storage materials: glycogen, triglyceride and protein, show 2 distinct maxima (spring, autumn).     

Sterol binding by OSBP-related protein 1L regulates late endosome motility and function

ORP1L is an oxysterol binding homologue that regulates late endosome (LE) positioning. We show that ORP1L binds several oxysterols and cholesterol, and characterize a mutant, ORP1L Δ560–563, defective in oxysterol binding. While wild-type ORP1L clusters LE, ORP1L Δ560–563 induces LE scattering, which is reversed by disruption of the endoplasmic reticulum (ER) targeting FFAT motif, suggesting that it is due to enhanced LE–ER interactions. Endosome motility is reduced upon overexpression of ORP1L. Both wild-type ORP1L and the Δ560–563 mutant induce the recruitment of both dynactin and kinesin-2 on LE. Most of the LE decorated by overexpressed ORP1L fail to accept endocytosed dextran or EGF, and the transfected cells display defective degradation of internalized EGF. ORP1L silencing in macrophage foam cells enhances endosome motility and results in inhibition of [³H]cholesterol efflux to apolipoprotein A-I. These data demonstrate that LE motility and functions in both protein and lipid transport are regulated by ORP1L.     

Pyrrolizidine alkaloids inDanaus plexippus L. andDanaus chrysippus L.

Summary Danaus plexippus L. andDanaus chrysippus L. have been found to store pyrrolizidine alkaloids obtained from adult food plants and it is suggested that the alkaloids contribute to the unpalatability of the butterflies to potential predators.Acknowledgment. We thank Dr.C. C. J. Culvenor for rearing some of the butterflies andJ. M. Smith for plant collection. The plants were identified by the national Herbarium, Melbourne.     

Immunocytology of alpha-endorphin positive hypothalamic fibers of Carassius auratus L. and Cyprinus carpio L.]

An immunocytological study of the basal hypothalamus of Carassius auratus and Cyprinus carpio with an alpha-endorphin antiserum shows the different nerve processes belonging probably to the immunoreactive cells of the lateral part of the N.L.T. According to their pathways, two main fibre tracts have been distinguished: many fluorescent fibres converge towards the pituitary gland into which they enter, other fibres run caudally through the tuber towards the nucleus tuberis inferior (Baumgarten and Braak) where they could not be followed further.     

Accumulation of indole glucosinolates inPsylliodes chrysocephala L.-infested,or-damaged tissues of oilseed rape (Brassica napus L.)

Summary Infestation of oilseed rape (Brassica napus L.) by the cabbage stem flea beetle (Psylliodes chrysocephala L.) leads to an overall reduction in the levels of aliphatic (alkenyl- and hydroxyalkenyl-) glucosinolates in the damaged tissue (lamina, petiole, stem) and a massive accumulation of indole glucosinolates. Whilst artificial damage (puncturing), with and without associated bacterial infection with an isolate fromP. chrysocephala, led to such accumulation, this was less than that observed in the insect-infected situation.     

L1CAM malfunction in the nervous system and human carcinomas

Research over the last 25 years on the cell adhesion molecule L1 has revealed its pivotal role in nervous system function. Mutations of the human L1CAM gene have been shown to cause neurodevelopmental disorders such as X-linked hydrocephalus, spastic paraplegia and mental retardation. Impaired L1 function has been also implicated in the aetiology of fetal alcohol spectrum disorders, defective enteric nervous system development and malformations of the renal system. Importantly, aberrant expression of L1 has emerged as a critical factor in the development of human carcinomas, where it enhances cell proliferation, motility and chemoresistance. This discovery promoted collaborative work between tumour biologists and neurobiologists, which has led to a substantial expansion of the basic knowledge about L1 function and regulation. Here we provide an overview of the pathological conditions caused by L1 malfunction. We further discuss how the available data on gene regulation, molecular interactions and posttranslational processing of L1 may contribute to a better understanding of associated neurological and cancerous diseases.     

Alkaloids ofConoclinium coelestinum (L.) DC.,Eupatorium compositifolium walt., andE. altissimum L.: Isolation of crystalline intermedine fromC. coelestinum

Summary The isolation of crystalline intermedine fromConoclinium, coelestinum (L.) DC., notmixed with the diastereoisomeric congener base lycopsamine, is reported.E. compositifolium Walt. yielded the usual mixture of intermedine and lycopsamine; fromE. altissimum L. rinderine and 7-angelylheliotridine have been isolated.     

Studies on the modification of Escherichia coli ribosomal protein L7/L12 by succinic anhydride

Lysine modification by increasing quantities of succinic anhydride in the Escherichia coli ribosomal protein L7/L12 produces loss of its ability in reconstitution of elongation-factor-G-dependent GTP hydrolysis and polyphenylalanine synthesis activities, showing lower antigenicity and loss of antigenic determinants.     

Astragalin ausPodophyllum peltatum L. undP. emodi Wall.

Summary A yellow flavonoid pigment, which occurs as a companion of the lignan glycosides inPodophyllum peltatum L. andP. emodi Wall. has been identified as astragalin (=kaempferol-3-glucoside).

---

---

18. Mitt. über mitoschemmende Naturstoffe. 17. Mitt.:E. Schreier, Helv. chim. Acta47, 1529 (1964).     

The nutritional status and radiosensitivity of someCicer arietinum L. Cultivars

Résumé Etat nutritif et radiosensibilité de 3 cultures deCicer arientum L. (C-612, Sanyasi et Chhola). Le pourcentage de protéine était de l'ordre de 19.9, 20.6 et 22.6 pour Sanyasi, C-612 et Chhola respectivement. Chez C-612 le niveau de lysine est bas et celui d'arginine élevé. Le rapport de pourcentage entre le total des acides aminés et les protéines fut le même dans toutes les cultures. Le C-612 était significativement (p>-0,05) plus résistant aux rayons gamma, comme l'ont montré les relations: dosage/germination et dosage/hauteur de plantule.

---

---

Acknowledgment. The help provided by Prof.C. W. Deyoe, Kansas State University, Kansas 66506, USA, for the nutritional estimations is gratefully acknowledged.     

Detection of nucleolus organizer regions (NOR) in the chromosomes of the domestic pig (Sus scrofa domestica L.)

In the domestic pig (Sus scrofa domestica L.) nucleolar organizer regions (NOR) were detected by a combined silver-Giemsa method (Ag-G). The main sites of NORs are the secondary constrictions of chromosomes 8 and 10. Sometimes an additional NOR was observed near the centromere of 1 homologue of chromosome 11. Association of NORs were seen only between chromosomes 10 and at a very low frequency.     

转录因子TCF7L2在HePG2细胞IDE表达调控中的作用

目的 TCF7L2是一种重要的转录因子,与2型糖尿病(T2DM)发生发展密切相关.本研究探讨慢病毒介导的RNA干扰抑制TCF7L2基因表达对人肝癌细胞株HePG2胰岛素降解酶(IDE)基因的影响.方法 以人TCF7L2 mRNA编码序列作为干扰靶点,构建TCF7L2特异性短发卡RNA慢病毒表达载体(LV-TCF7 L2-shRNA)感染HePG2细胞.应用实时定量PCR及Western blot检测转染后TCF7L2与IDE表达的变化.结果 成功构建TCF7L2 shRNA慢病毒载体LV-TCF7L2-shRNA.qPCR及Westem blot结果显示干扰组HePG2细胞TCF7L2和IDE mRNA及蛋白的表达水平较空白组及阴性对照组显著降低(P＜0.05).结论 LV-TCF7L2-shRNA载体有效地抑制了IDE的表达,结果证明TCF7L2是IDE表达调控中重要的转录因子,为探讨TCF7L2与IDE在2型糖尿病发病机制中的作用奠定了基础.     

Detection of nucleolus organizer regions (NOR) in the chromosomes of the domestic pig (Sus scrofa domestica L.)

Summary In the domestic pig (Sus scrofa domestica L.) nucleolar organizer regions (NOR) were detected by a combined silver-Giemsa method (Ag-G). The main sites of NORs are the secondary constrictions of chromosomes 8 and 10. Sometimes an additional NOR was observed near the centromere of 1 homologue of chromosome 11. Associations of NORs were seen only between chromosomes 10 and at a very low frequency.     

Chemical defence in the larvae of the leaf beetleGonioctena viminalis L. (Coleoptera: Chrysomelidae)

Summary The leaf beetle larva ofGonioctena (Phytodecta) viminalis L. has been shown to produce five volatile constituents within its paired abdominal defensive gland reservoirs. It is the first time that these compounds have been reported to occur in coleopteran defensive glands (linalool, phenylethanol) and Chrysomelidae larvae (6-methyl-5-hepten-2-one, 6-methyl-5-hepten-2-ol, 2-hexenal). In addition to the gross morphology of theGonioctena gland and its discharge behavior, the natural products found are discussed in terms of chemotaxonomy.     

L1Tc non-LTR retrotransposons from Trypanosoma cruzi contain a functional viral-like self-cleaving 2A sequence in frame with the active proteins they encode

A comparative analysis of 40 Trypanosoma cruzi L1Tc elements showed that the 2A self-cleaving sequence described in viruses is present in them. Of these elements, 72% maintain the canonical 2A motif (DxExNPGP). A high percentage has a conserved point mutation within the motif that has not been previously described. In vitro and in vivo expression of reporter polyproteins showed that the L1Tc2A sequence is functional. Mutations within certain L1Tc2A sequences affect the efficiency of the cleavage. The data indicate that the L1Tc2A sequence may be influencing the L1Tc enzymatic machinery determining the composition and level of the translated products. The residues located immediately upstream of the 2A consensus sequence increase the cleaving efficiency and appear to stabilize the relative amount of translated products. These authors contributed equally to this work. Received 26 January 2006; received after revision 11 April 2006; accepted 21 April 2006