| RRC ID |
6174
|
| 著者 |
Thalhammer A, Hundertmark M, Popova AV, Seckler R, Hincha DK.
|
| タイトル |
Interaction of two intrinsically disordered plant stress proteins (COR15A and COR15B) with lipid membranes in the dry state.
|
| ジャーナル |
Biochim Biophys Acta
|
| Abstract |
COR15A and COR15B form a tandem repeat of highly homologous genes in Arabidopsis thaliana. Both genes are highly cold induced and the encoded proteins belong to the Pfam LEA_4 group (group 3) of the late embryogenesis abundant (LEA) proteins. Both proteins were predicted to be intrinsically disordered in solution. Only COR15A has previously been characterized and it was shown to be localized in the soluble stroma fraction of chloroplasts. Ectopic expression of COR15A in Arabidopsis resulted in increased freezing tolerance of both chloroplasts after freezing and thawing of intact leaves and of isolated protoplasts frozen and thawed in vitro. In the present study we have generated recombinant mature COR15A and COR15B for a comparative study of their structure and possible function as membrane protectants. CD spectroscopy showed that both proteins are predominantly unstructured in solution and mainly alpha-helical after drying. Both proteins showed similar effects on the thermotropic phase behavior of dry liposomes. A decrease in the gel to liquid-crystalline phase transition temperature depended on both the unsaturation of the fatty acyl chains and lipid headgroup structure. FTIR spectroscopy indicated no strong interactions between the proteins and the lipid phosphate and carbonyl groups, but significant interactions with the galactose headgroup of the chloroplast lipid monogalactosyldiacylglycerol. These findings were rationalized by modeling the secondary structure of COR15A and COR15B. Helical wheel projection indicated the presence of amphipathic alpha-helices in both proteins. The helices lacked a clear separation of positive and negative charges on the hydrophilic face, but contained several hydroxylated amino acids.
|
| 巻・号 |
1798(9)
|
| ページ |
1812-20
|
| 公開日 |
2010-9-1
|
| DOI |
10.1016/j.bbamem.2010.05.015
|
| PII |
S0005-2736(10)00164-1
|
| PMID |
20510170
|
| MeSH |
Amino Acid Sequence
Arabidopsis / chemistry*
Arabidopsis Proteins / chemistry*
Circular Dichroism
Hydrogen Bonding
Hydrophobic and Hydrophilic Interactions
Membrane Lipids / chemistry*
Molecular Sequence Data
Protein Structure, Secondary
Sequence Alignment
Spectroscopy, Fourier Transform Infrared
|
| IF |
3.411
|
| 引用数 |
71
|
|
WOS 分野
|
BIOPHYSICS
BIOCHEMISTRY & MOLECULAR BIOLOGY
|
| リソース情報 |
| シロイヌナズナ / 植物培養細胞・遺伝子 |
pda06312
pda02804 |
