NaTrxh is an essential protein for pollen rejection in Nicotiana by increasing S-RNase activity.
Plant J
; 103(4): 1304-1317, 2020 08.
Article
em En
| MEDLINE
| ID: mdl-32392366
ABSTRACT
In self-incompatible Solanaceae, the pistil protein S-RNase contributes to S-specific pollen rejection in conspecific crosses, as well as to rejecting pollen from foreign species or whole clades. However, S-RNase alone is not sufficient for either type of pollen rejection. We describe a thioredoxin (Trx) type h from Nicotiana alata, NaTrxh, which interacts with and reduces S-RNase in vitro. Here, we show that expressing a redox-inactive mutant, NaTrxhSS , suppresses both S-specific pollen rejection and rejection of pollen from Nicotiana plumbaginifolia. Biochemical experiments provide evidence that NaTrxh specifically reduces the Cys155 -Cys185 disulphide bond of SC10 -Rnase, resulting in a significant increase of its ribonuclease activity. This reduction and increase in S-RNase activity by NaTrxh helps to explain why S-RNase alone could be insufficient for pollen rejection.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Plantas
/
Pólen
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Ribonucleases
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Nicotiana
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article