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Artigos
Publicados em Periódicos
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P100-00 Expression of
correctly processed human growth hormone in seeds of transgenic
tobacco plants Leite A, Kemper EL, Silva MJ, Luchessi AD,
Siloto RMP, Bonaccorsi ED, El-Dorry H, Arruda P* Human growth
hormone was expressed in transgenic tobacco seeds using the
monocot tissue-specific promoter from sorghum gamma-kafirin
seed storage protein gene. During tobacco seed ripening, the
expressed hormone was directed to the endoplasmic reticulum
by a signal peptide from a Coix prolamin and was secreted
into the apoplastic space, where it accounted for 0.16% of
total soluble seed protein. The expressed hormone has the
same amino acid sequence and receptor-binding properties as
the native mature hormone. Molecular Breeding 6: 47-53, 2000.
IF = 2.786 *E-mail: parruda@unicamp.br
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| P101-00
Making colony PCR easier by adding gel-loading buffer to the
amplification reaction Menossi M*, Cremonese N, Maron LG, Arruda
P* Here we evaluated the effects of three widely used gel-loading
buffers on the amplification of targets with different sizes,
from different sources and using several primer combinations.
Biotechniques 28: 424-425, 2000. IF = 1.749 *E-mail: menossi@unicamp.br;
parruda@unicamp.br
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| P102-00
Molecular evidence that sugarcane yellow leaf virus (ScYLV)
is a member of the Luteoviridae family Maia IG, Gonçalves MC,
Arruda P*, Vega J* A previously uncharacterized virus was reported
in southeast Brazil causing a yellowing leaf disease in sugarcane.
The virus, termed sugarcane yellow leaf virus (ScYLV), shares
features typical of the luteoviruses. The nucleotide sequence
of the coat protein (CP), 17 kDa protein and C-tenminus of the
RNA-dependent RNA polymerase coding regions was determined from
an RT-PCR amplification product. Comparisons showed that the
deduced amino acid sequences share a considerable degree of
identity and similarity with corresponding sequences of known
luteoviruses, thus clearly establishing ScYLV as a member of
the family Luteoviridae. The authenticity of the CP open reading
frame was confirmed by its expression in E. coli. The recombinant
CP positively reacted in immunoblot assays with polyclonal antibodies
raised against native ScYLV. Phylogenetic analyses also suggest
that the 5' and 3' coding blocks of the ScYLV genome possess
different taxonomic affinities within the Luteoviridae family,
as does also the genome of soybean dwarf virus. Archives of
Virology 145: 1009-1019, 2000. IF = 1.591 *E-mail: parruda@unicamp.br;
jvega@unicamp.br |
| P103-00
Regulation of lysine catabolism in higher plants Arruda P*,
Kemper EL, Papes F and Leite A Lysine is an important essential
amino acid for mammals, but its concentration in cereals, one
our main food sources, is low. Research over the past 40 years
has unraveled many biochemical and molecular details of the
aspartic acid pathway, which is the main route for lysine biosynthesis
in plants. However, genetic manipulation of this pathway has
not been successful at producing high-lysine seeds. This is
because lysine, instead of being accumulated, is degraded via
the saccharopine pathway. Recent work has increased our knowledge
of this pathway, including both the enzymes involved and their
regulation. Trends in Plant Science 5: 324-330, 2000. IF = 9.350
*E-mail: parruda@unicamp.br |
| P104-00
Degradation of lysine in rice seeds: Effect of calcium, ionic
strength, S-adenosylmethionine and S-2-aminoethyl-L-cysteine
on the lysine 2-oxoglutarate reductase-saccharopine dehydrogenase
bifunctional enzyme Gaziola SA, Sodek L, Arruda P*, Lea PJ and
Azevedo RA Lysine biosynthesis has been extensively studied
and the regulatory enzymes characterized in some of the most
important crop plants, however, much less is known about the
lysine degradation pathway. Lysine 2-oxoglutarate reductase
(LOR) and saccharopine dehydrogenase (SDN) have recently been
partially purified and characterized from plants, and have been
shown to exist as a single bifunctional polypeptide, We have
further characterized these enzymes from rice endosperm in relation
to Ca2+ and ionic strength modulation, Optimum pH values of
7.0 and 8.0 were obtained for LOR and SDH, respectively, It
would appear that the modulation by Ca2+ and ionic strength
of LOR is a common feature among plant LOR enzymes, S-adenosylmethionine
did not produce any significant effect on either enzyme activity,
indicating that it only plays a role in the regulation of lysine
biosynthesis. The effect of S-2-aminoethyl-L-cysteine (AEC)
as both a substrate and an inhibitor of LOR activity was also
tested, AEC was shown to partially substitute for lysine as
a substrate for LOR, but was also able to inhibit LOR activity.
The higher K-m for AEC compared to lysine may reflect a lower
binding affinity for AEC. Physiologia Plantarum, 110: 164- 171,
2000. IF = 2.460 *E-mail:parruda@unicamp.br |
| P105-00
The mitochondrial genome of the primary screwworm fly Cochliomyia
hominivorax (Diptera: Calliphoridae) Lessinger AC, Martins Junqueira
AC, Lemos TA, Kemper EL, Da Silva FR, Vettore AL, Arruda P,
L Azeredo-Espin AM* The complete sequence of the mitochondrial
genome of the screwworm Cochliomyia hominivorax was determined.
This genome is 16 022 bp in size and corresponds to a typical
Brachycera mtDNA. The nucleotide composition of C. hominivorax
mtDNA is 77% AT-rich, reflected in the predominance of AT-rich
codons in protein-coding genes. Non-optimal codon usage was
commonly observed in C. hominivorax mitochondrial genes. Phylogenetic
analysis distributed the Acalypterate species as a monophyletic
group and assembled the C. hominivorax (Calyptratae) and the
Acalyptratae in a typical Brachycera cluster. The identification
of diagnostic restriction sites on the sequenced mitochondrial
genome and the correlation with previous RFLP analysis are discussed.
Insect Molecular Biology 5:521-529, 2000. IF = 2.412 *E-mail:
azeredo@unicamp.br |
| P106-00
An Arabidopsis gene induced by wounding functionaly homologous
to flavoprotein oxidoreductases Costa CL, Arruda P*, Benedetti
CE The regulation of genes in response to wounding is mediated
in part by the octadecanoids 12-oxo-phytodienoic acid (OPDA),
jasmonic acid (JA) and its methyl ester methyl jasmonate (MeJA).
We identified, by differential display, an Arabidopsis gene
(OPR3) induced after wounding. OPR3 is homologous to members
of the flavin mononucleotide (FMN) binding proteins. Transcripts
of OPR3 rapidly accumulated in leaves after wounding and MeJA
treatment, but they were detected in various tissues of unwounded
plants at relatively low levels. Expression of the OPR3 gene
was significantly reduced in wounded leaves of the coi1 mutant,
indicating partial dependence on jasmonate perception for full
induction of the gene. The recombinant OPR3 protein also showed
beta -NADPH oxidation activity in the presence of cyclohexenone,
but not cyclohexanone, suggesting that the enzyme has specificity
to cleavage of olefinic bonds in cyclic enones. The results
show that the OPR3 gene product represents a new OPR of Arabidopsis
induced after wounding. Plant Molecular Biology, 44: 61-71,
2000. IF = 3.102 *E-mail: parruda@unicamp.br
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| P107-00
Improved analysis of promoter activity in biolistically transformed
plant cells Menossi M, Puigdomènech P, Martínez-Izquierdo JA
Transient assays using particle bombardment are a powerful way
to rapidly evaluate gene expression in intact plant tissues.
We developed an approach to decrease data dispersion and also
evaluated the consistency of the two assays of GUS activity
used to determine the promoter activity in transient assays.
This approach uses three genes (C1, B-Peru and GFP) and decreases
data variability considerably. Moreover, it avoids a loss of
time and money in the evaluation of non transformed and poorly
transformed samples. Our results also show that the histochemical
spot counting method for the quantification of promoter-driven
GUS activity, may understimate the activity of strong promoters.
For this reason, the fluorometric assay is to be preferred when
quantifying promoter-driven GUS activity. Biotechniques 28:
54-58, 2000. IF = 1.749 *E-mail: menossi@unicamp.br |
| P108-00
Total lipids and fatty acids of strains of Metarhizium anisopliae
Pupin AM, Messias CL*, Piedrabuena AE, Roberts DW Two growth
stages, conidia (C) and mycelium (M), and two media, minimal
medium (MM) and complete medium (MC), were compared in 10 strains
of M. anisopliae, and two strains of M. anisopliae var. majus
were similar in percentages of total lipids. Tukey test for
average of lipid content in conidia (C) and mycelia (M) cultured
on minimal (MM) and complete (MC) media showed significant differences
between means at the 5% level for mycelia and conidia, indicating
variability in total lipid production and storage during growth.
Strains 5 and 7, both variety majus, did not present sizable
differences from variety anisopliae. For fatty acids, C18:1
and C18:2, oleic and linoleic, respectively, the differences
were all highly significant (p= 1%) with the highest means being
obtained for conidia for fatty acid C18:1 and for myclelia for
fatty acid C18:2. Brazilian Journal of Microbiology 31:121-128,
2000. *E-mail: cmessias@unicamp.br |
| P109-00
Violacein cytotoxicity and induction of apoptosis in V79 cells
Melo PD, Maria SS, Vidal BC, Haun M*, Duran N Cytotoxicity and
induction of apoptosis by violacein, a pigment potentially effective
for the treatment of Chagas' disease and leukemia and lymphoma
cells in culture were studied in V79 cells subjected to the
TUNEL assay and the Feulgen reaction followed by image analysis.
The drug was found to trigger apoptosis but not necrosis, strengthening
its potential as a therapeutic agent. In Vitro Cellular & Developmental
Biology - Animal 36(8): 539-543, 2000. IF = 1.066 *E-mail: marcela@reitoria.unicamp.br
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