PLANT JOURNAL
·
2018
·Vol. 94
·期 2
·288-303
·
IF 5.775
Jie Qian,Yueyue Chen,Ying Hu,Yingtian Deng,Yang Liu,Gang Li,Wenxuan Zou,Jie Zhao
Summary Replication factor C (RFC) is a conserved eukaryotic complex consisting of RFC1/2/3/4/5. It plays important roles in DNA replication and the cell cycle in yeast and fruit fly. However, it is not very clear how RFC subunits function in higher plants, except for the Arabidopsis ( At ) subunits AtRFC1 and AtRFC3 . In this study, we investigated the functions of AtRFC4 and found that loss of function of AtRFC4 led to an early sporophyte lethality that initiated as early as the elongated zygote stage, all defective embryos arrested at the two- to four-cell embryo proper stage, and the endosperm possessed six to eight free nuclei. Complementation of rfc4-1 /+ with AtRFC4 expression driven through the embryo-specific DD45pro and ABI3pro or the endosperm-specific FIS2pro could not completely restore the defective embryo or endosperm, whereas a combination of these three promoters in rfc4-1 /+ enabled the aborted ovules to develop into viable seeds. This suggests that AtRFC4 functions simultaneously in endosperm and embryo and that the proliferation of endosperm is critical for embryo maturation. Assays of DNA content in rfc4-1 /+ verified that DNA replication was disrupted in endosperm and embryo, resulting in blocked mitosis. Moreover, we observed a decreased proportion of late S-phase and M-phase cells in the rfc4-1 /– FIS 2; DD 45; ABI 3pro::At RFC 4 seedlings, suggesting that incomplete DNA replication triggered cell cycle arrest in cells of the root apical meristem. Therefore, we conclude that AtRFC4 is a crucial gene for DNA replication.
研究领域:
植物学
·
遗传学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
AGRONOMY JOURNAL
·
2019
·Vol. 111
·期 5
·2341-2349
·
IF 1.805
Jing Li,Yin Min Htwe,Yong Wang,Yaodong Yang,Yi Wu,Dongxia Li,Abdul Kareem,Rencai Wang
Haustorium absorbs energy from the endosperms (liquid and solid) and plays a key role in nutrient mobilization during coconut germination and seedling growth. This study was conducted to shed light on possible interactions between haustorium and endosperms during this process. Germination rates and morphological changes of coconut cultivars Hainan Tall (HT) and Red Dwarf (RD), as well as the profiles of sugars and fatty acids in endosperms and haustorium were also analyzed. Results showed that liquid and solid endosperm inside the coconut exhausts successively, while haustorium occupies the nut gradually. Haustorium had significant positive correlation with seedling, while it had significant negative correlation with liquid and solid endosperms. Sugars in liquid endosperm continuously decreased, whereas in solid endosperm and haustorium accumulated at early stages and decreased later along with the aggressive seedling growth. Fatty acids in solid endosperm shared a very similar trend with sugars. In conclusion, haustorium development and seedling growth mainly depend on the nutrients stored in the liquid endosperm at early stages and then depend on the solid endosperm, in which fatty acids degrade rapidly to sugar so as to provide enough energy. These findings could be applicable in coconut germination and seedling propagation. Core Ideas Relative cool season (25–29°C) is more suitable for coconut germination and local variety (HT) is more adaptable. Development mainly depends on stored nutrients in liquid endosperm at early stages and then on solid endosperm. Fatty acids in solid endosperm degrade rapidly to sugars since liquid endosperm almost exhausted. Conversion of fatty acids to sugars helps provide enough energy for rapidly growing haustorium and seedling.
研究领域:
植物生理学
·
植物营养学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2014
·
IF 3.259
Huihui Ti,Qing Li,Ruifen Zhang,Mingwei Zhang,Yuanyuan Deng,Zhencheng Wei,Jianwei Chi,Yan Zhang
This study quantified free and bound phytochemicals and their antioxidant activity in the endosperm and bran/embryo of different indica rice varieties. Phytochemicals mainly existed as free form in the bran/embryo and as both free and bound forms in the endosperm. The average values of total phenolic content, flavonoid content, FRAP, ABTS and ORAC values in the bran/embryo were 3.1, 10.4, 8.2, 11.2 and 11.4 times higher than those in the endosperm, respectively. In whole brown rice, the bran contributed 59.2%, 53.7%, 47.7%, 55.5% and 56.9% of total phenolics, flavonoids, FRAP, ABTS and ORAC values, respectively. Seven individual phenolics (gallic, protocatechuic, chlorogenic, caffeic, syringic, coumaric and ferulic acids) were detected with most coumaric and ferulic acids in the bran. All measurements exhibited varietal differences. These findings provide important information for improving human health by encouraging the consumption of whole brown rice and its use in food product development.
研究领域:
食品科学
·
植物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
PeerJ
·
2018
·
IF 2.118
Faheem Afzal Shah,Jun Ni,Jing Chen,Qiaojian Wang,Wenbo Liu,Xue Chen,Caiguo Tang,Songling Fu,Lifang Wu
Sapium sebiferum , an ornamental and bio-energetic plant, is propagated by seed. Its seed coat contains germination inhibitors and takes a long time to stratify for germination. In this study, we discovered that the S. sebiferum seed coat (especially the tegmen) and endospermic cap (ESC) contained high levels of proanthocyanidins (PAs). Seed coat and ESC removal induced seed germination, whereas exogenous application with seed coat extract (SCE) or PAs significantly inhibited this process, suggesting that PAs in the seed coat played a major role in regulating seed germination in S. sebiferum . We further investigated how SCE affected the expression of the seed-germination-related genes. The results showed that treatment with SCE upregulated the transcription level of the dormancy-related gene, gibberellins (GAs) suppressing genes, abscisic acid (ABA) biosynthesis and signalling genes. SCE decreased the transcript levels of ABA catabolic genes, GAs biosynthesis genes, reactive oxygen species genes and nitrates-signalling genes. Exogenous application of nordihydroguaiaretic acid, gibberellic acid, hydrogen peroxide and potassium nitrate recovered seed germination in seed-coat-extract supplemented medium. In this study, we highlighted the role of PAs, and their interactions with the other germination regulators, in the regulation of seed dormancy in S. sebiferum .
研究领域:
植物学
·
植物生理学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）