Two aspartic proteases, BnaAP36s and BnaAP39s, regulate pollen tube guidance in Brassica napus

© The Author(s), under exclusive licence to Springer Nature B.V. 2023. Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law..

Pollen tube (PT) growth towards the micropyle is critical for successful double fertilization. However, the mechanism of micropyle-directed PT growth is still unclear in Brassica napus. In this study, two aspartate proteases, BnaAP36s and BnaAP39s, were identified in B. napus. BnaAP36s and BnaAP39s were localized to the plasma membrane. The homologues of BnaAP36 and BnaAP39 were highly expressed in flower organs, especially in the anther. Sextuple and double mutants of BnaAP36s and BnaAP39s were then generated using CRISPR/Cas9 technology. Compared to WT, the seed-set of cr-bnaap36 and cr-bnaap39 mutants was reduced by 50% and 60%, respectively. The reduction in seed-set was also found when cr-bnaap36 and cr-bnaap39 were used as the female parent in a reciprocal cross assay. Like WT, cr-bnaap36 and cr-bnaap39 pollen were able to germinate and the relative PTs were able to elongate in style. Approximately 36% and 33% of cr-bnaap36 and cr-bnaap39 PTs, respectively, failed to grow towards the micropyle, indicating that BnaAP36s and BnaAP39s are essential for micropyle-directed PT growth. Furthermore, Alexander's staining showed that 10% of cr-bnaap39 pollen grains were aborted, but not cr-bnaap36, suggesting that BnaAP39s may also affect microspore development. These results suggest that BnaAP36s and BnaAP39s play a critical role in the growth of micropyle-directed PTs in B. napus.

Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01377-1.

Medienart:

E-Artikel

Erscheinungsjahr:

2023

Erschienen:

2023

Enthalten in:

Zur Gesamtaufnahme - volume:43

Enthalten in:

Molecular breeding : new strategies in plant improvement - 43(2023), 4 vom: 12. Apr., Seite 27

Sprache:

Englisch

Beteiligte Personen:

Wang, Lulin [VerfasserIn]
Liang, Xiaomei [VerfasserIn]
Dou, Shengwei [VerfasserIn]
Yi, Bin [VerfasserIn]
Fu, Tingdong [VerfasserIn]
Ma, Chaozhi [VerfasserIn]
Dai, Cheng [VerfasserIn]

Links:

Volltext

Themen:

BnaAP36s
BnaAP39s
Brassica napus
CRISPR/Cas9
Journal Article
Pollen tube guidance
Seed-set

Anmerkungen:

Date Revised 06.04.2024

published: Electronic-eCollection

Citation Status PubMed-not-MEDLINE

doi:

10.1007/s11032-023-01377-1

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM358151856