The Temperature-Dependent Retention of Introns in GPI8 Transcripts Contributes to a Drooping and Fragile Shoot Phenotype in Rice

Abstract

Attachment of glycosylphosphatidylinositols (GPIs) to the C-termini of proteins is one of the most common posttranslational modifications in eukaryotic cells. GPI8/PIG-K is the catalytic subunit of the GPI transamidase complex catalyzing the transfer en bloc GPI to proteins. In this study, a T-DNA insertional mutant of rice with temperature-dependent drooping and fragile (df) shoots phenotype was isolated. The insertion site of the T-DNA fragment was 879 bp downstream of the stop codon of the OsGPI8 gene, which caused introns retention in the gene transcripts, especially at higher temperatures. A complementation test confirmed that this change in the OsGPI8 transcripts was responsible for the mutant phenotype. Compared to control plants, internodes of the df mutant showed a thinner shell with a reduced cell number in the transverse direction, and an inhomogeneous secondary wall layer in bundle sheath cells, while many sclerenchyma cells at the tops of the main veins of df leaves were shrunken and their walls were thinner. The df plants also displayed a major reduction in cellulose and lignin content in both culms and leaves. Our data indicate that GPI anchor proteins play important roles in biosynthesis and accumulation of cell wall material, cell shape, and cell division in rice.

Uncovering dynamic evolution in the plastid genome of seven Ligusticum species provides insights into species discrimination and phylogenetic implications

“…Overall, a moderate divergence among sequences was demonstrated, compared to several genera recently reported 44 , 61 , 68 – 70 . Of note, petA-psbJ-psbL , the most divergent region revealed in the present study, has also been demonstrated to be highly divergent in many genera 68 , 69 , 71 , 72 . Even though high diversity was observed in trnH-psbA and ycf1 , which have extensively suggested to be taken as universal barcodes 73 and depicted has a capacity for sufficient variation information for taxon discrimination in angiosperms 72 , 74 , no one hotspot alone was enough to distinguish these seven herbs.…”

Electronic cigarette aerosols alter the expression of cisplatin transporters and increase drug resistance in oral cancer cells

“…The principal mechanism of cisplatin cytotoxicity is the formation of platinum–DNA adducts. Thus cellular mechanisms leading to a reduction in cisplatin-induced DNA damage are key factors in the development of cisplatin resistance 41 . The majority of cisplatin-induced DNA lesions, intra-strand adducts, and inter-strand crosslinks are removed by nucleotide excision repair.…”

“…Moreover, the bulk of cisplatin is actively moved in and out of the cell by copper transporters (CTR1, ATP7A and ATP7B) 44 . Nonetheless, the following ATP-binding cassette (ABC) ATPase genes ABCG2, ABCC2, ABCA1 , and ABCC1 have been associated with cisplatin resistance in diverse cancers 41 , 44 – 47 Thus, we investigated the mRNA expression levels of CTR1 , ATP7A , ATP7B , ABCG2, ABCC2, ABCA1 , and ABCC1 after exposure to e-cigarette extracts alone without cisplatin. Following 48 h of e-cigarette exposure, we observed that the expression of the copper transporter CTR1 , which mediates the uptake of cisplatin, was down-regulated at the mRNA level in WSU-HN6 for all e-cigarette extracts tested, but remained unchanged in the other cell lines (Figure S3 a).…”

O6-methylguanine-DNA methyltransferase modulates cisplatin-induced DNA double-strand breaks by targeting the homologous recombination pathway in nasopharyngeal carcinoma

“…Since the development of CDDP in the 1970s, this platinum-based chemotherapy drug has shown promising anticancer efficacy in a variety of cancers, including NPC. In addition to monotherapy, combination treatment with CDDP and other anticancer therapies, such as radiotherapy and other chemotherapy drugs, is also a common therapeutic strategy in cancer patients because of its synergistic effect against tumor growth [ 8 , 9 ]. Even with the advances in immunotherapy, combination treatment with CDDP and an immune checkpoint inhibitor has demonstrated survival benefits in patients with a certain type of cancer, including head and neck cancer [ 8 , 31 , 32 ].…”

“…CDDP, a platinum-based anticancer agent, is effective against several types of human cancers [ 8 , 9 ]. In general, CDDP can induce apoptotic cell death through platinum–DNA adduct formation.…”