Isolation of a novel G-protein gamma-subunit from Arabidopsis thaliana and its interaction with G beta

There is increasing evidence that heterotrimeric G-proteins (G-proteins) are involved in many plant processes including phytohormone response, pathogen defence and stomatal control. In animal systems, each of the three G-protein subunits belong to large multigene families; however, few subunits have been isolated from plants. Here we report the cloning of a second plant G-protein γ-subunit (AGG2) from Arabidopsis thaliana. The predicted AGG2 protein sequence shows 48% identity to the first identified Arabidopsis Gγ-subunit, AGG1. Furthermore, AGG2 contains all of the conserved characteristics of γ-subunits including a small size (100 amino acids, 11.1 kDa), C-terminal CAAX box and a N-terminal α-helix region capable of forming a coiled-coil interaction with the β-subunit. A strong interaction between AGG2 and both the tobacco (TGB1) and Arabidopsis (AGB1) β-subunits was observed in vivo using the yeast two-hybrid system. The strong association between AGG2 and AGB1 was confirmed in vitro. Southern and Northern analyses showed that AGG2 is a single copy gene in Arabidopsis producing two transcripts that are present in all tissues tested. The isolation of a second γ-subunit from A. thaliana indicates that plant G-proteins, like their mammalian counterparts, may form different heterotrimer combinations that presumably regulate multiple signal transduction pathways.

ELECTROPHORETIC ANALYSIS OF 11 ENZYMES IN NATURAL POPULATIONS OFROOT, 1926 (DIPTERA: CULICIDAE) IN THE AMAZON REGION

Of eleven proteins analyzed in four Amazonian populations, the esterases showed the greatest variation, with five activity zones. EST1, EST2 and EST5 showed variation in each of the populations studied. EST1 and EST2 are each controlled by two, and EST5 by four, codomi-nant alleles. LAP presented six activity zones, with codominant variation in LAP5and LAP6.oc—GPDH was monomorphic with one activity band on starch gel and two on polyacrylamide gel. 1DH presented two activity zones, with variation in the IDHl region. PGM had a single activity zone, with variation in all populations. The Ariquemes populations showed five alleles and the other populations three, all of then codominant. Three activity zones with two codominant alleles were observed for ODH. Aldehyde Oxidase showed two activity zones, with variation in AOl only in the Ariquemes and Porto Velho/Samuel populations. 6-PGDH showed only one activity zone and variation only in the Ariquemes population. The remaing systems - XDH, G-6-PDH and GDH. was monomorphic.

Biologia e controle microbiano de Urbanus acawoios (Williams, 1926) (Lepidoptera: Hesperiidae): II. patologia e susceptibilidade em larvas infectadas por Bacillus thuringiensis Var. kurstaki (H-3a:3b)

Devido à falta de informações sobre Urbanus acawoios (Williams, 1926) (Lepidoptera: Hesperiidae), e pelos danos severos por ele causados em árvores de Clitoria racemosa, o presente trabalho foi desenvolvido sob condições de laboratório para verificar a possibilidade de utilizar Bacillus thuringiensis var. kurstaki (H-3a:3b) como agente microbiano para o seu controle. O pH do intestino médio do hesperídeo mostrou ser bastante alcalino, variando de 8,4 a 9,2 (média de 8,7), indicando a possibilidade das larvas serem susceptíveis ao patógeno. Os ensaios confirmaram a alta susceptibilidade a dosagens equivalentes a 110 g / ha, resultando em tempos letais medianos (TL50) de 42,28, 37,18, 28,00 e 51,87 horas para larvas de 3o, 4°, início e final do 5º ínstares, respectivamente. Três outras dosagens (80, 150 e 280 g/h) foram aplicadas para larvas do 3º ínstar, resultando em TLs50 de 42,62, 30,77 e 30,06 horas, respectivamente. Descrições detalhadas sobre os sintomas externos nas larvas infectadas foram dadas. As alterações histológicas do intestino médio afetado pela d-endotoxina de B. thuringiensis foram descritas. Os resultados obtidos no presente trabalho revelam a grande possibilidade de controlar esta praga utilizando-se produtos e formulados à base desta bactéria.

Prodromus Florae Peninsulae Indiae Orientalis :containing abridged descriptions of the plants found in the peninsula of British India, arranged according to the natural system : Vol. 1 /by Robert Wight and G.A. Walker-Arnott.

1834

A general history of the dichlamydeous plants :comprising complete descriptions of the different orders...the whole arranged according to the natural system /by George Don.

1831 v.1

A general history of the dichlamydeous plants :comprising complete descriptions of the different orders...the whole arranged according to the natural system /by George Don.

1834 v.3

A general history of the dichlamydeous plants :comprising complete descriptions of the different orders...the whole arranged according to the natural system /by George Don.

1838 v.4

A general history of the dichlamydeous plants :comprising complete descriptions of the different orders...the whole arranged according to the natural system /by George Don.

1832 v.2

Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita /auctoribus G. Bentham et J.D. Hooker.

v.1:pt.1 (1862)

Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita /auctoribus G. Bentham et J.D. Hooker.

v.1:pt.2 (1865)

Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita /auctoribus G. Bentham et J.D. Hooker.

v.1:pt.3 (1867)

Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita /auctoribus G. Bentham et J.D. Hooker.

v.2:pt.1 (1873)

Genera plantarum :ad exemplaria imprimis in Herberiis Kewensibus servata definita /auctoribus G. Bentham et J.D. Hooker.

v.2:pt.2 (1876)