INVESTIGADORES
VIOLA Ivana Lorena
artículos
Título:
Interaction of the BELL-like protein ATH1 with DNA : role of homeodomain residue 54 in specifying the different binding properties of BELL and KNOX proteins
Autor/es:
IVANA L. VIOLA; DANIEL H. GONZALEZ
Revista:
BIOLOGICAL CHEMISTRY
Editorial:
de Gruyter
Referencias:
Lugar: Berlín; Año: 2006 vol. 387 p. 31 - 40
ISSN:
1431-6730
Resumen:
Abstract
We have studied the interaction of the BELL-like Arabidopsis homeodomain protein ATH1
with DNA. Analysis of olig onucleotides selected by the ATH1 homeodomain from a random
mixture suggests that ATH1 preferentially binds the sequence TGACAGGT. Single nucleotide
replacements at positions 2 or 3 of this sequence abolish binding, while changes at position 4
are more tolerated. Changes outside this core differentially affect binding depending on the
position. Hydroxyl radical footprinting and missing nucleoside experiments showed that ATH1
interacts with a 7-bp region of the strand carrying the GAC core. On the other strand, protection
was observed along a 7-bp region, comprising one additional nucleotide complementary to T in
position 1. A comparative analysis of the binding preferences of the homeodomains of ATH1
and STM (a KNOX homeodomain protein) indicated that they bind similar sequences with
differences in affinity and specificity. The decreased affinity displayed by the ATH1
homeodomain correlates with the presence of valine, instead of lysine as in STM, at position 54.
This difference also explains the decreased and increased selectivities, respectively, at positions
4 and 5. The results obtained point to an essential role of residue 54 in determining the different
binding properties of BELL and KNOX homeodomains.
with DNA. Analysis of olig onucleotides selected by the ATH1 homeodomain from a random
mixture suggests that ATH1 preferentially binds the sequence TGACAGGT. Single nucleotide
replacements at positions 2 or 3 of this sequence abolish binding, while changes at position 4
are more tolerated. Changes outside this core differentially affect binding depending on the
position. Hydroxyl radical footprinting and missing nucleoside experiments showed that ATH1
interacts with a 7-bp region of the strand carrying the GAC core. On the other strand, protection
was observed along a 7-bp region, comprising one additional nucleotide complementary to T in
position 1. A comparative analysis of the binding preferences of the homeodomains of ATH1
and STM (a KNOX homeodomain protein) indicated that they bind similar sequences with
differences in affinity and specificity. The decreased affinity displayed by the ATH1
homeodomain correlates with the presence of valine, instead of lysine as in STM, at position 54.
This difference also explains the decreased and increased selectivities, respectively, at positions
4 and 5. The results obtained point to an essential role of residue 54 in determining the different
binding properties of BELL and KNOX homeodomains.
with DNA. Analysis of olig onucleotides selected by the ATH1 homeodomain from a random
mixture suggests that ATH1 preferentially binds the sequence TGACAGGT. Single nucleotide
replacements at positions 2 or 3 of this sequence abolish binding, while changes at position 4
are more tolerated. Changes outside this core differentially affect binding depending on the
position. Hydroxyl radical footprinting and missing nucleoside experiments showed that ATH1
interacts with a 7-bp region of the strand carrying the GAC core. On the other strand, protection
was observed along a 7-bp region, comprising one additional nucleotide complementary to T in
position 1. A comparative analysis of the binding preferences of the homeodomains of ATH1
and STM (a KNOX homeodomain protein) indicated that they bind similar sequences with
differences in affinity and specificity. The decreased affinity displayed by the ATH1
homeodomain correlates with the presence of valine, instead of lysine as in STM, at position 54.
This difference also explains the decreased and increased selectivities, respectively, at positions
4 and 5. The results obtained point to an essential role of residue 54 in determining the different
binding properties of BELL and KNOX homeodomains.
Arabidopsis homeodomain protein ATH1
with DNA. Analysis of olig onucleotides selected by the ATH1 homeodomain from a random
mixture suggests that ATH1 preferentially binds the sequence TGACAGGT. Single nucleotide
replacements at positions 2 or 3 of this sequence abolish binding, while changes at position 4
are more tolerated. Changes outside this core differentially affect binding depending on the
position. Hydroxyl radical footprinting and missing nucleoside experiments showed that ATH1
interacts with a 7-bp region of the strand carrying the GAC core. On the other strand, protection
was observed along a 7-bp region, comprising one additional nucleotide complementary to T in
position 1. A comparative analysis of the binding preferences of the homeodomains of ATH1
and STM (a KNOX homeodomain protein) indicated that they bind similar sequences with
differences in affinity and specificity. The decreased affinity displayed by the ATH1
homeodomain correlates with the presence of valine, instead of lysine as in STM, at position 54.
This difference also explains the decreased and increased selectivities, respectively, at positions
4 and 5. The results obtained point to an essential role of residue 54 in determining the different
binding properties of BELL and KNOX homeodomains.