| 35 matches found in 11 documents. Search time: 0.002 seconds. |
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Score: 12.00 |
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| Title: Investigation of stability and disulfide bond shuffling of lipid transfer proteins by molecular dynamics simulation .
| | Author: Allison JR Moll GP van Gunsteren WF | | Journal: Biochemistry Citation: V : 49 P : 6916-27 Year: 2010 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub20695529 Accession (PMID): 20695529 | | Abstract: Proteins comprising each of the two plant nonspecific lipid transfer protein ( LTP ) families , LTP1s and LTP2s , share similar folds and biological functions and are stabilized by four native disulfide bonds .
Disulfide-scrambling experiments suggested that rice LTP2 is more thermostable than rice LTP1 and identified multiple disulfide-scrambled isomers for LTP1 but only one for LTP2 .
According to the potential energy evaluated in two GROMOS force fields , however , rice LTP1 is more stable than either rice or wheat LTP2 .
Moreover , the published rice LTP2 NMR model structure is found to be highly unfavorable .
The reasons for this are investigated , and it is found that the rice LTP2 sequence is in fact more compatible with the more ordered X-ray structure of wheat LTP2 than with the published rice LTP2 NMR model structure .
The proposed disulfide bond shuffling of rice LTP1 , rice LTP2 , and , for comparative purposes , wheat LTP2 and a homology model combining the rice LTP2 sequence with the wheat LTP2 structure is then investigated with a computational disulfide-scrambling technique .
| Matching Sentences:
[ Sen. 6, subscore: 4.00 ]: The proposed disulfide bond shuffling of rice LTP1 , rice LTP2 , and , for comparative purposes , wheat LTP2 and a homology model combining the rice LTP2 sequence with the wheat LTP2 structure is then investigated with a computational disulfide-scrambling technique .
[ Sen. 5, subscore: 3.00 ]: The reasons for this are investigated , and it is found that the rice LTP2 sequence is in fact more compatible with the more ordered X-ray structure of wheat LTP2 than with the published rice LTP2 NMR model structure .
[ Sen. 2, subscore: 2.00 ]: Disulfide-scrambling experiments suggested that rice LTP2 is more thermostable than rice LTP1 and identified multiple disulfide-scrambled isomers for LTP1 but only one for LTP2 .
[ Sen. 1, subscore: 1.00 ]: Proteins comprising each of the two plant nonspecific lipid transfer protein ( LTP ) families , LTP1s and LTP2s , share similar folds and biological functions and are stabilized by four native disulfide bonds .
[ Sen. 3, subscore: 1.00 ]: According to the potential energy evaluated in two GROMOS force fields , however , rice LTP1 is more stable than either rice or wheat LTP2 .
[ Sen. 4, subscore: 1.00 ]: Moreover , the published rice LTP2 NMR model structure is found to be highly unfavorable .
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Score: 9.00 |
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| Title: The promoter of the barley aleurone-specific gene encoding a putative 7 kDa lipid transfer protein confers aleurone cell-specific expression in transgenic rice .
| | Author: Kalla R Shimamoto K Potter R Nielsen PS Linnestad C Olsen OA .
| | Journal: Plant J Citation: V : 6 ( 6 ) P : 849-60 Year: 1994 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub7849757 Accession (PMID): 7849757 | | Abstract: This paper describes the aleurone-specific gene Ltp2 from barley , which encodes a putative 7 kDa non-specific lipid transfer protein .
As shown by Northern and in situ hybridization analyses , the Ltp2 transcript is present in barley aleurone cells shortly after the initiation of aleurone cell differentiation .
The expression of Ltp2 increases until grain mid-maturity , but the mRNA is absent from mature grains .
The Ltp2 transcript is undetectable in the embryo and vegetative it issues , confirming the aleurone specificity of the Ltp2 gene .
The ability of the isolated 801 bp Ltp2 promoter to direct aleurone-specific expression in immature barley grains is demonstrated by particle bombardment experiments .
In these experiments , the activity of the Ltp2 promoter is 5% of the activity of the strong constitutive Actin1 promoter from rice , as quantified by GUS activity measurements .
In stably transformed rice plants containing the Ltp2 promoter-Gus construct , the specificity of the Ltp2 promoter is confirmed in vivo by the presence of GUS activity exclusively in the aleurone layer .
This study demonstrates the conserved nature of the regulatory signals involved in aleurone-specific gene transcription in cereal grains . | Matching Sentences:
[ Sen. 4, subscore: 2.00 ]: The Ltp2 transcript is undetectable in the embryo and vegetative it issues , confirming the aleurone specificity of the Ltp2 gene .
[ Sen. 7, subscore: 2.00 ]: In stably transformed rice plants containing the Ltp2 promoter-Gus construct , the specificity of the Ltp2 promoter is confirmed in vivo by the presence of GUS activity exclusively in the aleurone layer .
[ Sen. 1, subscore: 1.00 ]: This paper describes the aleurone-specific gene Ltp2 from barley , which encodes a putative 7 kDa non-specific lipid transfer protein .
[ Sen. 2, subscore: 1.00 ]: As shown by Northern and in situ hybridization analyses , the Ltp2 transcript is present in barley aleurone cells shortly after the initiation of aleurone cell differentiation .
[ Sen. 3, subscore: 1.00 ]: The expression of Ltp2 increases until grain mid-maturity , but the mRNA is absent from mature grains .
[ Sen. 5, subscore: 1.00 ]: The ability of the isolated 801 bp Ltp2 promoter to direct aleurone-specific expression in immature barley grains is demonstrated by particle bombardment experiments .
[ Sen. 6, subscore: 1.00 ]: In these experiments , the activity of the Ltp2 promoter is 5% of the activity of the strong constitutive Actin1 promoter from rice , as quantified by GUS activity measurements .
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Score: 7.00 |
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| Title: Silencing of the aleurone-specific Ltp2-gus gene in transgenic rice is reversed by transgene rearrangements and loss of aberrant transcripts .
| | Author: Morino K Olsen OA Shimamoto K | | Journal: Plant Cell Physiol .
Citation: V : 45 ( 10 ) P : 1500-8 Year: 2004 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15564533 Accession (PMID): 15564533 | | Abstract: An Ltp2 promoter was isolated from barley as an aleurone-specific promoter , and its it issue specificity was maintained in transgenic rice .
Expression of the Ltp2-gus gene in rice could be detected by X-gluc staining of the seeds .
Previously , we reported the isolation of silenced plants in the R2 generation and the involvement of antisense gus transcripts in aleurone-specific Ltp2-gus gene silencing in transgenic rice , the L3 . 3 line .
In the current study , we analyzed the L0 . 1 line , a sibling of the L3 . 3 line , and the partially revertant line from the L0 . 1 line accompanied by a transgene structural change .
Strong silencing of the Ltp2-gus gene was detected over five generations in the L0 . 1 line .
DNA and RNA analysis revealed that there were incomplete transgenes and that several aberrant RNAs that carried an antisense gus region were expressed in the L0 . 1 line .
Determination of the transgene structure in the L0 . 1 line revealed that the partial antisense gus gene and the partial Ltp2 promoter region fused to the Ltp2 promoter were lacking in the revertants .
RNA analysis demonstrated that the antisense gus and the promoter transcripts were produced and found in the poly ( A ) - fraction .
Results of these analyses suggested that the observed aberrant transcripts , including antisense and promoter transcripts , were associated with Ltp2-gus silencing in the L0 . 1 line . | Matching Sentences:
[ Sen. 7, subscore: 2.00 ]: Determination of the transgene structure in the L0 . 1 line revealed that the partial antisense gus gene and the partial Ltp2 promoter region fused to the Ltp2 promoter were lacking in the revertants .
[ Sen. 1, subscore: 1.00 ]: An Ltp2 promoter was isolated from barley as an aleurone-specific promoter , and its it issue specificity was maintained in transgenic rice .
[ Sen. 2, subscore: 1.00 ]: Expression of the Ltp2-gus gene in rice could be detected by X-gluc staining of the seeds .
[ Sen. 3, subscore: 1.00 ]: Previously , we reported the isolation of silenced plants in the R2 generation and the involvement of antisense gus transcripts in aleurone-specific Ltp2-gus gene silencing in transgenic rice , the L3 . 3 line .
[ Sen. 5, subscore: 1.00 ]: Strong silencing of the Ltp2-gus gene was detected over five generations in the L0 . 1 line .
[ Sen. 9, subscore: 1.00 ]: Results of these analyses suggested that the observed aberrant transcripts , including antisense and promoter transcripts , were associated with Ltp2-gus silencing in the L0 . 1 line .
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Score: 5.00 |
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| Title: Distinct unfolding and refolding pathways of lipid transfer proteins LTP1 and LTP2 .
| | Author: Lin CH Li L Lyu PC Chang JY .
| | Journal: Protein J Citation: V : 23 ( 8 ) P : 553-66 Year: 2004 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15648977 Accession (PMID): 15648977 | | Abstract: Plant non-specific lipid transfer proteins ( ns-LTPs ) comprise two families , LTP1s and LTP2s , all structurally stabilized by four native disulfide bonds .
Solution and crystal structures of both LTP1s and LTP2s from various plants have been determined .
Despite the similarities of their biological function and backbone folds , the biophysical properties of LTP1s and LTP2s differ significantly .
In this report , the mechanisms of unfolding and refolding of rice LTP1 and LTP2 have been investigated using the technique of disulfide bonds scrambling .
LTP1 is shown to unfold and refold via predominant species of partially structured intermediates .
Four isomers of partly unfolded and extensively unfolded LTP1 were identified , isolated and their disulfide structures were determined .
By contrast , unfolding and refolding of LTP2 adopt a ( close to ) two-state mechanism , and undergo a reversible conversion between the native and a single extensively unfolded isomer without accumulation of any significant intermediate . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Plant non-specific lipid transfer proteins ( ns-LTPs ) comprise two families , LTP1s and LTP2s , all structurally stabilized by four native disulfide bonds .
[ Sen. 2, subscore: 1.00 ]: Solution and crystal structures of both LTP1s and LTP2s from various plants have been determined .
[ Sen. 3, subscore: 1.00 ]: Despite the similarities of their biological function and backbone folds , the biophysical properties of LTP1s and LTP2s differ significantly .
[ Sen. 4, subscore: 1.00 ]: In this report , the mechanisms of unfolding and refolding of rice LTP1 and LTP2 have been investigated using the technique of disulfide bonds scrambling .
[ Sen. 7, subscore: 1.00 ]: By contrast , unfolding and refolding of LTP2 adopt a ( close to ) two-state mechanism , and undergo a reversible conversion between the native and a single extensively unfolded isomer without accumulation of any significant intermediate .
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Score: 3.00 |
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| Title: Silencing of an aleurone-specific gene in transgenic rice is caused by a rearranged transgene .
| | Author: Morino K Olsen OA Shimamoto K | | Journal: Plant J Citation: V : 17 ( 3 ) P : 275-85 Year: 1999 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub10097385 Accession (PMID): 10097385 | | Abstract: In rice , silencing of the aleurone-specific Ltp2-gus transgene , causing easily detectable staining patterns on the grain surface , offers a convenient tool to study quantitative aspects of gene silencing in monocots .
In this paper we analyzed phenotypes , occurrence , inheritance and environmental effects on the silencing .
We also report on the cloning of transgenes , determination of their structure and analysis of transcripts from the transgene loci .
The results show that various patterns of silencing appeared in the R2 generation at which most of the transgenes became homozygous and that they were inherited for five generations .
In addition , silencing independently occurred in three generations and reversion to full expression was also found .
Cloning of transgenes from a silenced L3 . 3 line demonstrated that this line carried two transgene loci : one carried an intact Ltp2-gus gene and the other carried a rearranged transgene in which part of the gus gene was in the antisense orientation .
Analysis of gus transcripts indicated that partial antisense RNA derived from the rearranged transgene was present in silenced lines and was polyadenylated but that it was absent in non-silenced lines .
RNA analyses suggested that the Ltp2-gus silencing in the aleurone layer was post-transcriptional and that it may be caused by interaction of partial antisense gus transcripts with normal sense transcripts .
Possible involvement of antisense transcripts in post-transcriptional silencing is discussed . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: In rice , silencing of the aleurone-specific Ltp2-gus transgene , causing easily detectable staining patterns on the grain surface , offers a convenient tool to study quantitative aspects of gene silencing in monocots .
[ Sen. 6, subscore: 1.00 ]: Cloning of transgenes from a silenced L3 . 3 line demonstrated that this line carried two transgene loci : one carried an intact Ltp2-gus gene and the other carried a rearranged transgene in which part of the gus gene was in the antisense orientation .
[ Sen. 8, subscore: 1.00 ]: RNA analyses suggested that the Ltp2-gus silencing in the aleurone layer was post-transcriptional and that it may be caused by interaction of partial antisense gus transcripts with normal sense transcripts .
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Score: 3.00 |
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| Title: A pair of genes coding for lipid-transfer proteins in Sorghum vulgare .
| | Author: Pelse-Siebenbourg F Caelles C Kader JC Delseny M Puigdomnech P | | Journal: Gene Citation: V : 148 ( 2 ) P : 305-8 Year: 1994 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub7958959 Accession (PMID): 7958959 | | Abstract: Approximately five genes coding for lipid-transfer proteins ( LTP ) can be detected in Sorghum vulgare by DNA blots using a specific genomic probe .
Two of these genes have been identified and sequenced .
The two genes ( ltp1 and ltp2 ) code for very similar ( 91 . 8% identity ) proteins , they are separated by approx .
4 kb of DNA and their open reading frames may be read in the same direction .
The gene ( ltp1 ) located upstream has an intron placed in the same position already described for other ltp in maize and rice .
Gene ltp2 has no intron . cDNAs corresponding to ltp1 have been identified in a 6-day-old plantlet library , but not for ltp2 .
The results of the comparison between the two sequences indicate the presence of a gap between the two genes in their promoter region .
LTP seem to be coded for in plants by a small family of genes .
At least in sorghum , two of its components are tightly clustered in the same genomic region .
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[ Sen. 6, subscore: 2.00 ]: Gene ltp2 has no intron . cDNAs corresponding to ltp1 have been identified in a 6-day-old plantlet library , but not for ltp2 .
[ Sen. 3, subscore: 1.00 ]: The two genes ( ltp1 and ltp2 ) code for very similar ( 91 . 8% identity ) proteins , they are separated by approx .
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Score: 2.00 |
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| Title: Characterization of a gene encoding an abscisic acid-inducible type-2 lipid transfer protein from rice .
| | Author: Garca-Garrido JM Menossi M Puigdomnech P Martnez-Izquierdo JA Delseny M | | Journal: FEBS Lett .
Citation: V : 428 ( 3 ) P : 193-9 Year: 1998 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub9654133 Accession (PMID): 9654133 | | Abstract: The cloning and sequence analysis of a novel gene that encodes a type 2 non-specific lipid transfer-like protein ( LTP ) from rice is reported .
Sequence analysis revealed an ORF encoding a protein showing characteristics of the LTP proteins .
However , rice LTP2 is more similar to heterologous LTPs than to rice LTP1 , supporting the existence of two distinct families of plant LTPs .
Ltp2 mRNA is accumulated only in mature seeds .
In vegetative it issues , mRNA was only detected after treatment with abscisic acid ( ABA ) , mannitol or NaCl .
Transient expression experiments that the 61 nucleotides upstream of the TATA box , containing two ACGT boxes and the motif I , are sufficient for ABA responsiveness of the Ltp gene . | Matching Sentences:
[ Sen. 3, subscore: 1.00 ]: However , rice LTP2 is more similar to heterologous LTPs than to rice LTP1 , supporting the existence of two distinct families of plant LTPs .
[ Sen. 4, subscore: 1.00 ]: Ltp2 mRNA is accumulated only in mature seeds .
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Score: 1.00 |
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| Title: Identification of a 49-bp fragment of the HvLTP2 promoter directing aleurone cell specific expression .
| | Author: Opsahl-Sorteberg HG Divon HH Nielsen PS Kalla R Hammond-Kosack M Shimamoto K Kohli A | | Journal: Gene Citation: V : 341 ( ) P : 49-58 Year: 2004 Type: ARTICLE | | Literature: oryza Field: abstract Doc ID: pub15474287 Accession (PMID): 15474287 | | Abstract: Identification of regulatory elements directing definite and specific spatiotemporal expression patterns is a prerequisite to the next generation of transgenic plants with commercial and ethical feasibility for producing plantibodies or other pharmaceutically important compounds .
Here we describe the functional dissection of the barley nonspecific lipid transfer protein gene promoter , HvLTP2 .
The gene is specifically expressed in aleurone cells of cereals and used as an aleurone marker in maize and rice .
The transcript is uniformly localised in the barley aleurone cells from around 10 DAP .
Patchy expression in aleurone cells of transgenic rice has been reported and explained by silencing of transgenes .
We have performed deletion analyses of the 801-bp HvLTP2 promoter to gain insight into the molecular basis of its regulation and the presence of putative regulatory elements .
From the deletion studies , a 49-bp promoter region directing aleurone-specific expression was identified .
Simultaneously , in vivo footprinting was carried out to identify promoter elements bound by putative regulatory proteins .
Within the 49-bp fragment , the most promising candidate for a minimal cis-acting regulatory region directing aleurone specificity is the ds-sequence .
Based on our results , we hypothesise that the ds-sequence directs aleurone specificity , possibly through a concerted action with elements directing general expression in the seed .
Moreover , we present an overview of LTP2 elements putatively involved in directing seed , endosperm , and aleurone expression .
Additionally , we report HvLTP2 expression in the embryo , not previously detected .
The regulatory element ( s ) directing expression in embryo is located downstream of the 49-bp fragment directing aleurone specificity , thus demonstrating independent control of aleurone and embryo-localised expression .
Finally , we discuss the existence of several endosperm-specific boxes and whether alternative promoter elements and combinations of them may direct aleurone expression , explaining why comparing different genes expressed in aleurone fail to identify only one required , common promoter element . | Matching Sentences:
[ Sen. 11, subscore: 1.00 ]: Moreover , we present an overview of LTP2 elements putatively involved in directing seed , endosperm , and aleurone expression .
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Score: 1.00 |
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| Title: OsC6 , encoding a lipid transfer protein , is required for postmeiotic anther development in rice .
| | Author: Zhang D Liang W Yin C Zong J Gu F Zhang D | | Journal: Plant Physiol Citation: V : 154 P : 149-62 Year: 2010 Type: MEDLINE | | Literature: oryza Field: abstract Doc ID: pub20610705 Accession (PMID): 20610705 | | Abstract: Synthesis of lipidic components in anthers , including of the pollen exine , is essential for plant male reproductive development .
Plant lipid transfer proteins ( LTPs ) are small , abundant lipid-binding proteins that have the ability to exchange lipids between membranes in vitro .
However , their biological role in male reproductive development remains less understood .
Here , we report the crucial role of OsC6 in regulating postmeiotic anther development in rice ( Oryza sativa ) .
Found in monocots , OsC6 belongs to a distinct clade from previously identified LTP1 and LTP2 family members found in both dicots and monocots .
OsC6 expression is mainly detectable in tapetal cells and weakly in microspores from stage 9 to stage 11 of anther development .
Immunological assays indicated that OsC6 is widely distributed in anther it issues such as the tapetal cytoplasm , the extracellular space between the tapetum and middle layer , and the anther locule and anther cuticle .
Biochemical assays indicated that recombinant OsC6 has lipid binding activity .
Moreover , plants in which OsC6 was silenced had defective development of orbicules ( ie Ubisch bodies ) and pollen exine and had reduced pollen fertility .
Furthermore , additional evidence is provided that the expression of OsC6 is positively regulated by a basic helix-loop-helix transcription factor , Tapetum Degeneration Retardation ( TDR ) .
Extra granule-like structures were observed on the inner surface of the tdr tapetal layer when the expression of OsC6 was driven by the TDR promoter compared with the tdr mutant .
These data suggest that OsC6 plays a crucial role in the development of lipidic orbicules and pollen exine during anther development in rice .
| Matching Sentences:
[ Sen. 5, subscore: 1.00 ]: Found in monocots , OsC6 belongs to a distinct clade from previously identified LTP1 and LTP2 family members found in both dicots and monocots .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
Score: 1.00 |
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| Title: Silencing of the aleurone-specific Ltp2-gus gene in transgenic rice is reversed by transgene rearrangements and loss of aberrant transcripts .
| | Author: Morino K Olsen OA Shimamoto K | | Journal: Plant Cell Physiol .
Citation: V : 45 ( 10 ) P : 1500-8 Year: 2004 Type: ARTICLE | | Literature: oryza Field: title Doc ID: pub15564533 Accession (PMID): 15564533 | | Abstract: An Ltp2 promoter was isolated from barley as an aleurone-specific promoter , and its it issue specificity was maintained in transgenic rice .
Expression of the Ltp2-gus gene in rice could be detected by X-gluc staining of the seeds .
Previously , we reported the isolation of silenced plants in the R2 generation and the involvement of antisense gus transcripts in aleurone-specific Ltp2-gus gene silencing in transgenic rice , the L3 . 3 line .
In the current study , we analyzed the L0 . 1 line , a sibling of the L3 . 3 line , and the partially revertant line from the L0 . 1 line accompanied by a transgene structural change .
Strong silencing of the Ltp2-gus gene was detected over five generations in the L0 . 1 line .
DNA and RNA analysis revealed that there were incomplete transgenes and that several aberrant RNAs that carried an antisense gus region were expressed in the L0 . 1 line .
Determination of the transgene structure in the L0 . 1 line revealed that the partial antisense gus gene and the partial Ltp2 promoter region fused to the Ltp2 promoter were lacking in the revertants .
RNA analysis demonstrated that the antisense gus and the promoter transcripts were produced and found in the poly ( A ) - fraction .
Results of these analyses suggested that the observed aberrant transcripts , including antisense and promoter transcripts , were associated with Ltp2-gus silencing in the L0 . 1 line . | Matching Sentences:
[ Sen. 1, subscore: 1.00 ]: Silencing of the aleurone-specific Ltp2-gus gene in transgenic rice is reversed by transgene rearrangements and loss of aberrant transcripts .
| | Supplemental links/files: reference in endnote online text related articles pubmed citation | |
