Table 1. Proteins Enriched in the LDs of Tobacco Pollen Tubes.
| Protein Type | Name | Gene ID | iBAQ ‰ | Enrichment |
|---|---|---|---|---|
| Caleosin1 | NtCLO1a | LOC107783728 | 158 ± 10 | 1234 |
| Oleosin1 | NtOLE6b | LOC107824536 | 64 ± 30 | 2137 |
| Caleosin | NtCLO1b | LOC107817909 | 40 ± 5 | 993 |
| Oleosin | NtOLE6a | LOC107780677 | 35 ± 16 | 6746 |
| LDAP1 | NtLDAP1a | LOC107765167 | 28 ± 3 | 741 |
| Cycloartenol synthase1 | NtCASb | LOC107762593 | 16 ± 4 | 1517 |
| Plant UBX domain-containing protein1 | NtPUX10c | LOC107769345 | 15 ± 3 | 341 |
| LDAP | NtLDAP1b | LOC107804268 | 7.0 ± 0.5 | n.d. in controls |
| LDAP | NtLDAP3a | LOC107827582 | 5.0 ± 0.4 | 557 |
| Cycloartenol synthase | NtCASa | LOC107826198 | 4.1 ± 1.2 | 2605 |
| Sterol methyltransferase 11 | NtSMT1c | LOC107813194 | 3.1 ± 0.3 | 219 |
| Unknown protein | NtPTLD1 | LOC107815104 | 2.8 ± 0.02 | n.d. in controls |
| Oil body lipase | NtOBL1 | LOC107788962 | 2.6 ± 0.9 | 307 |
| Plant UBX domain-containing protein | NtPUX10a | LOC107799924 | 2.2 ± 0.3 | n.d. in controls |
| LDIP1 | NtLDIPa | LOC107763626 | 1.8 ± 0.8 | n.d. in controls |
| Unknown protein | NtPTLD3 | LOC107796437 | 1.7 ± 0.8 | 249 |
| Retinol dehydrogenase2 | NtFEY1 | LOC107800303 | 1.2 ± 4 | 1087 |
| LDIP | NtLDIPb | LOC107831283 | 1.1 ± 1.6 | n.d. in controls |
| Arfaptin domain-containing protein2 | NtADCP | LOC107827250 | 3.0 ± 0.6 | 9 |
| PLAT domain-containing protein3 | NtPDCP | LOC107793109 | 2.2 ± 0.6 | 10 |
| Small G protein3 | NtRABB1b | LOC107771805 | 1.12 ± 0.16 | 36 |
| Unknown protein1 | NtPTLD4 | LOC107778489 | 0.7 ± 0.2 | n.d. in controls |
| Carotenoid cleavage dioxygenase3 | NtCCD | LOC107830214 | 0.45 ± 0.08 | 245 |
| Small G protein3 | NtRAB2c | LOC107794510 | 0.13 ± 0.11 | 15 |
LDs were isolated from tobacco pollen tubes. Their protein composition (n = 3 biological replicates) was compared to total extracts and a cytosolic fraction (both n = 4) by LC-MS/MS after a tryptic in-gel digest. iBAQ values were determined using MaxQuant software. The relative iBAQ values were calculated as ‰ of all proteins in one sample. The enrichments were each determined from the LD iBAQ ‰ value divided by the higher value of the total and cytosolic fractions. Only proteins with an enrichment factor of >100 and making up more than 1 ‰ of the total iBAQ values were considered for the upper part of the list. Further proteins analyzed in respect to their localization are depicted in the lower part. For a list of all identified proteins, see Supplemental Data Set 1. Several corresponding cDNAs were cloned and transiently expressed as mVenus fusions in tobacco pollen tubes:
protein localized to LDs (1), protein localized to the ER (2), and protein that did not localize to the LDs or the ER (3). The “±” indicates sd. n.d., not detected.