Characterization of differential expression and leader intron function of Arabidopsis atTOC159 homologous genes by transgenic plants

Plastidial glycolipids contain diacylglycerol (DAG) moieties, which are either synthesized in the plastids (prokaryotic lipids) or originate in the extraplastidial compartment (eukaryotic lipids) necessitating their transfer into plastids. In contrast, the only phospholipid in plastids, phosphatidylglycerol (PG), contains exclusively prokaryotic DAG backbones. PG contributes in several ways to the functions of chloroplasts, but it is not known to what extent its prokaryotic nature is required to fulfill these tasks. As a first step toward answering this question, we produced transgenic tobacco plants that contain eukaryotic PG in thylakoids. This was achieved by targeting a bacterial DAG kinase into chloroplasts in which the heterologous enzyme was also incorporated into the envelope fraction. From lipid analysis we conclude that the DAG kinase phosphorylated eukaryotic DAG forming phosphatidic acid, which was converted into PG. This resulted in PG with 2–3 times more eukaryotic than prokaryotic DAG backbones. In the newly formed PG the unique Δ3-trans-double bond, normally confined to 3-trans-hexadecenoic acid, was also found in sn-2-bound cis-unsaturated C18 fatty acids. In addition, a lipidomics technique allowed the characterization of phosphatidic acid, which is assumed to be derived from eukaryotic DAG precursors in the chloroplasts of the transgenic plants. The differences in lipid composition had only minor effects on measured functions of the photosynthetic apparatus, whereas the most obvious phenotype was a significant reduction in growth.

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Characterization of the ‘Oat-Like Rice’ Caused by a Novel Allele OsMADS1Olr Reveals Vital Importance of OsMADS1 in Regulating Grain Shape in Oryza sativa L.

Rice ◽

10.1186/s12284-020-00428-x ◽

2020 ◽

Vol 13 (1) ◽

Author(s):

Penghui Li ◽

Hui Li ◽

Zhijian Liu ◽

Yong Zhuang ◽

Ming Wei ◽

...

Keyword(s):

Transgenic Plants ◽

Point Mutation ◽

Grain Shape ◽

Dominant Negative Effect ◽

Mads Box ◽

Grain Development ◽

Seed Setting ◽

Seed Setting Rate ◽

Novel Allele

Abstract Background Grain shape is a critical agronomic trait affecting grain yield and quality. Exploration and functional characterization of grain shape-related genes will facilitate rice breeding for higher quality and yield. Results Here, we characterized a recessive mutant named Oat-like rice for its unique grain shape which highly resembles oat grains. The Oat-like rice displayed abnormal floral organs, an open hull formed by remarkably elongated leafy lemmas and paleae, occasionally formed conjugated twin brown rice, an aberrant grain shape and a low seed setting rate. By map-based cloning, we discovered that Oat-like rice harbors a novel allele of OsMADS1 gene (OsMADS1Olr), which has a spontaneous point mutation that causes the substitution of an amino acid that is highly conserved in the MADS-box domain of the MADS-box family. Further linkage analysis indicated that the point mutation in the OsMADS1Olr is associated with Oat-like rice phenotype, and expression analysis of the OsMADS1 by qRT-PCR and GUS staining also indicated that it is highly expressed in flower organs as well as in the early stages of grain development. Furthermore, OsMADS1Olr-overexpressing plants showed similar phenotypes of Oat-like rice in grain shape, possibly due to the dominant negative effect. And OsMADS1-RNAi plants also displayed grain phenotypes like Oat-like rice. These results suggested that OsMADS1Olr is responsible for the Oat-like rice phenotype including aberrant grain shape. Moreover, the expression levels of representative genes related to grain shape regulation were apparently altered in Oat-like rice, OsMADS1Olr-overexpressing and OsMADS1-RNAi transgenic plants. Finally, compared with Oat-like rice, OsMADS1Olr-overexpressing and OsMADS1-RNAi plants, mild phenotype of seed-specific OsMADS1-RNAi transgenic plants indicated that OsMADS1 may has has a direct regulation role in grain development and the grain phenotypes of Oat-like rice, OsMADS1Olr-overexpressing and OsMADS1-RNAi plants are majorly caused by the abnormal lemma and palea development. Conclusions Altogether, our results showed that grain shape and a low seed setting rate of the notable ‘Oat-like rice’ are caused by a spontaneous point mutation in the novel allele OsMADS1Olr. Furthermore, our findings suggested that OsMADS1 mediates grain shape possibly by affecting the expression of representative genes related to grain shape regulation. Thus, this study not only revealed that OsMADS1 plays a vital role in regulating grain shape of rice but also highlighted the importance and value of OsMADS1 to improve the quality and yield of rice by molecular breeding.

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Identification and characterization of five cspA homologous genes from Myxococcus xanthus

Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression ◽

10.1016/s0167-4781(99)00164-5 ◽

1999 ◽

Vol 1447 (2-3) ◽

pp. 357-365 ◽

Cited By ~ 4

Author(s):

Kunitoshi Yamanaka ◽

Masayori Inouye ◽

Sumiko Inouye

Keyword(s):

Myxococcus Xanthus ◽

Homologous Genes ◽

Identification And Characterization

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Characterization of Agents That Induce Acquired Resistance by Transgenic Plants

Journal of Pesticide Science ◽

10.1584/jpestics.26.296 ◽

2001 ◽

Vol 26 (3) ◽

pp. 296-299 ◽

Cited By ~ 5

Author(s):

Yuriko WATAKABE ◽

Sachiko ONO ◽

Kazuyuki HIRATSUKA

Keyword(s):

Transgenic Plants ◽

Acquired Resistance

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Functional characterization of Lilium lancifolium cold-responsive Zinc Finger Homeodomain (ZFHD) gene in abscisic acid and osmotic stress tolerance

PeerJ ◽

10.7717/peerj.11508 ◽

2021 ◽

Vol 9 ◽

pp. e11508

Author(s):

Yubing Yong ◽

Yue Zhang ◽

Yingmin Lyu

Keyword(s):

Abscisic Acid ◽

Transgenic Plants ◽

Zinc Finger ◽

Promoter Region ◽

Salt Water ◽

Functional Characterization ◽

Regulatory Elements ◽

Response Analysis ◽

Lilium Lancifolium

Background. We have previously performed an analysis of the cold-responsive transcriptome in the mature leaves of tiger lily (Lilium lancifolium) by gene co-expression network identification. The results has revealed that a ZFHD gene, notated as encoding zinc finger homeodomain protein, may play an essential regulating role in tiger lily response to cold stress. Methods. A further investigation of the ZFHD gene (termed as LlZFHD4) responding to osmotic stresses, including cold, salt, water stresses, and abscisic acid (ABA) was performed in this study. Based on the transcriptome sequences, the coding region and 5′ promoter region of LlZFHD4 were cloned from mature tiger lily leaves. Stress response analysis was performed under continuous 4 °C, NaCl, PEG, and ABA treatments. Functional characterization of LlZFHD4 was conducted in transgenic Arabidopsis, tobacco, and yeast. Results. LlZFHD4 encodes a nuclear-localized protein consisting of 180 amino acids. The N-terminal region of LlZFHD4 has transcriptional activation activity in yeast. The 4 °C, NaCl, PEG, and ABA treatments induced the expression of LlZFHD4. Several stress- or hormone-responsive cis-acting regulatory elements (T-Box, BoxI. and ARF) and binding sites of transcription factors (MYC, DRE and W-box) were found in the core promoter region (789 bp) of LlZFHD4. Also, the GUS gene driven by LlZFHD4 promoter was up-regulated by cold, NaCl, water stresses, and ABA in Arabidopsis. Overexpression of LlZFHD4 improved cold and drought tolerance in transgenic Arabidopsis; higher survival rate and better osmotic adjustment capacity were observed in LlZFHD4 transgenic plants compared to wild type (WT) plants under 4 °C and PEG conditions. However, LlZFHD4 transgenic plants were less tolerant to salinity and more hypersensitive to ABA compared to WT plants. The transcript levels of stress- and ABA-responsive genes were much more up-regulated in LlZFHD4 transgenic Arabidopsis than WT. These results indicate LlZFHD4 is involved in ABA signaling pathway and plays a crucial role in regulating the response of tiger lily to cold, salt and water stresses.

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