PPR21 is involved in the splicing of nad2 introns via interacting with PPR-small MutS-related 1 and small PPR protein 2 and is essential to maize seed development.

Pentatricopeptide repeat (PPR) proteins are a large group of eukaryote-specific RNA-binding proteins that play pivotal roles in plant organelle gene expression. Here, we report the function of PPR21 in mitochondrial intron splicing and its role in maize kernel development. PPR21 is a typical P-type PPR protein targeted to mitochondria.

The DEAD-box RNA helicase ZmRH48 is required for the splicing of multiple mitochondrial introns, mitochondrial complex biosynthesis, and seed development in maize.

RNA helicases participate in nearly all aspects of RNA metabolism by rearranging RNAs or RNA-protein complexes in an adenosine triphosphate-dependent manner. Due to the large RNA helicase families in plants, the precise roles of many RNA helicases in plant physiology and development remain to be clarified. Here, we show that mutations in maize (Zea mays) DEAD-box RNA helicase 48 (ZmRH48) impair the splicing of mitochondrial introns, mitochondrial complex biosynthesis, and seed development.

GRP23 plays a core role in E-type editosomes via interacting with MORFs and atypical PPR-DYWs in mitochondria.

Identifying the PPR-E+-NUWA-DYW2 editosome improves our understanding of the C-to-U RNA editing in plant organelles. However, the mechanism of RNA editing remains to be elucidated. Here, we report that GLUTAMINE-RICH PROTEIN23 (GRP23), a previously identified nuclear transcription regulator, plays an essential role in mitochondrial RNA editing through interacting with MORF (multiple organellar RNA-editing factor) proteins and atypical DYW-type pentatricopeptide repeat (PPR) proteins.

PPR-DYW Protein EMP17 Is Required for Mitochondrial RNA Editing, Complex III Biogenesis, and Seed Development in Maize.

The conversion of cytidines to uridines (C-to-U) at specific sites in mitochondrial and plastid transcripts is a post-transcriptional processing event that is important to the expression of organellar genes. Pentatricopeptide repeat (PPR) proteins are involved in this process. In this study, we report the function of a previously uncharacterized PPR-DYW protein, Empty pericarp17 (EMP17), in the C-to-U editing and kernel development in maize.

ZmPPR26, a DYW-type pentatricopeptide repeat protein, is required for C-to-U RNA editing at atpA-1148 in maize chloroplasts.

Pentatricopeptide repeat (PPR) proteins are involved in the C-to-U RNA editing of organellar transcripts. The maize genome contains over 600 PPR proteins and few have been found to function in the C-to-U RNA editing in chloroplasts. Here, we report the function of ZmPPR26 in the C-to-U RNA editing and chloroplast biogenesis in maize.

EMP32 is required for the -splicing of intron 2 and seed development in maize.

Pentatricopeptide repeat (PPR) proteins play an important role in post-transcriptional regulation of mitochondrial gene expression. Functions of many PPR proteins and their roles in plant growth and development remain unknown. Through characterization of an () mutant, we identified the function of in mitochondrial intron splicing and seed development in maize.

PPR14 Interacts With PPR-SMR1 and CRM Protein Zm-mCSF1 to Facilitate Mitochondrial Intron Splicing in Maize.

In plants, splicing of organellar group II introns involves numerous nucleus-encoded factors. But, how these factors function and interact is not well understood. Here we report the function of a pentatricopeptide repeat (PPR) protein PPR14 and its physical relationship with other splicing factors in mitochondria.

DEK46 performs C-to-U editing of a specific site in mitochondrial nad7 introns that is critical for intron splicing and seed development in maize.

The self-splicing of group II introns during RNA processing depends on their catalytic structure and is influenced by numerous factors that promote the formation of that structure through direct binding. Here we report that C-to-U editing at a specific position in two nad7 introns is essential to splicing, which also implies that the catalytic activity of non-functional group II introns could be restored by editing. We characterized a maize (Zea mays) mutant, dek46, with a defective kernel phenotype; Dek46 encodes a pentatricopeptide repeat DYW protein exclusively localized in mitochondria.

PPR20 Is Required for the cis-Splicing of Mitochondrial nad2 Intron 3 and Seed Development in Maize.

Pentatricopeptide repeat (PPR) proteins are helical repeat RNA-binding proteins that function in RNA processing by conferring sequence-specific RNA-binding activity. Owing to the lethality of PPR mutants, functions of many PPR proteins remain obscure. In this study, we report the function of PPR20 in intron splicing in mitochondria and its role in maize seed development.

SMALL KERNEL4 is required for mitochondrial cox1 transcript editing and seed development in maize.

In land plants, cytidine-to-uridine (C-to-U) editing of organellar transcripts is an important post-transcriptional process, which is considered to remediate DNA genetic mutations to restore the coding of functional proteins. Pentatricopeptide repeat (PPR) proteins have key roles in C-to-U editing. Owing to its large number, however, the biological functions of many PPR proteins remain to be identified.

SMK6 mediates the C-to-U editing at multiple sites in maize mitochondria.

The recently identified PPR-E+/NVWA/DYW2 RNA editing complex provides insights into the mechanism of RNA editing in higher plant organelles. However, whether the complex works together with the previously identified editing factors RIPs/MORFs is unclear. In this paper, we identified a maize Smk6 gene, which encodes a mitochondrion-targeted PPR-E+protein with E1 and E2 domains at the C terminus.

The mitochondrial pentatricopeptide repeat protein EMP12 is involved in the splicing of three nad2 introns and seed development in maize.

Plant mitochondrial genes contain cis- and trans-group II introns that must be spliced before translation. The mechanism by which these introns are spliced is not well understood. Several families of proteins have been implicated in the intron splicing, of which the pentatricopeptide repeat (PPR) proteins are proposed to confer the substrate binding specificity.

The pentatricopeptide repeat protein EMPTY PERICARP8 is required for the splicing of three mitochondrial introns and seed development in maize.

Splicing of plant organellar group II introns is under accurate nuclear control that employs many nucleus-encoded protein cofactors from various families. For mitochondrial introns, only a few splicing factors have been characterized because disruption of their functions often causes embryo lethality. Here, we report the function of Empty Pericarp8 (Emp8) in the splicing of three group II introns in mitochondria, complex I biogenesis, and seed development in maize.

Encodes a Glutaminase in Vitamin B Biosynthesis Essential for Maize Seed Development.

Vitamin B, an essential cofactor for a range of biochemical reactions and a potent antioxidant, plays important roles in plant growth, development, and stress tolerance. Vitamin B deficiency causes embryo lethality in Arabidopsis (), but the specific role of vitamin B biosynthesis in endosperm development has not been fully addressed, especially in monocot crops, where endosperm constitutes the major portion of the grain. Through molecular characterization of a () mutant in maize, we reveal that vitamin B has differential effects on embryogenesis and endosperm development in maize.

The pentatricopeptide repeat protein EMP9 is required for mitochondrial ccmB and rps4 transcript editing, mitochondrial complex biogenesis and seed development in maize.

Pentatricopeptide repeat (PPR) proteins comprise a large family of sequence-specific RNA binding proteins in land plants. Because of its large family size and frequent embryo lethality in the mutants, molecular functions and physiological roles of many PPR proteins are unknown. Through characterization of an empty pericarp9 (emp9) mutant in maize (Zea mays), we defined the functions of EMP9 in mitochondrial RNA editing, respiratory complex formation and seed development.

A distal ABA responsive element in AtNCED3 promoter is required for positive feedback regulation of ABA biosynthesis in Arabidopsis.

The plant hormone abscisic acid (ABA) plays a crucial role in plant development and responses to abiotic stresses. Recent studies indicate that a positive feedback regulation by ABA exists in ABA biosynthesis in plants under dehydration stress. To understand the molecular basis of this regulation, we analyzed the cis-elements of the AtNCED3 promoter in Arabidopsis.

[Efficacy and adverse effets of nimotuzumab plus palitaxel liposome and carboplatin in the treatment for advanced non-small cell lung cancer].

Objective: To evaluate the efficacy of nimotuzumab combined with palitaxel liposome and carboplatin (LP) regimen for treatment of advanced non-small cell lung cancer (NSCLC), and to observe the changes of tumor markers and toxicities in the treatment. METHODS Forty-one patients with advanced NSCLC were randomly divided into 2 groups: 21 patients in the observation group were treated with nimotuzumab (200 mg per week for 6 weeks), palitaxel liposome 160 mg/m2 and carboplatin (AUC = 6). 20 patients in the control group were given LP regimen.

In vivo and in vitro characterization of site-specific recombination of actinophage R4 integrase.

The site-specific integrase of actinophage R4 belongs to the serine recombinase family. During the lysogenization process, it catalyzes site-specific recombination between the phage genome and the chromosome of Streptomyces parvulus 2297. An in vivo assay using Escherichia coli cells revealed that the minimum lengths of the recombination sites attB and attP are 50-bp and 49-bp, respectively, for efficient intramolecular recombination.

[rh-endostatin in combination with docetaxel and carboplatin as adjuvant treatment for non-small lung cancer].

Objective: To evaluate the efficacy of Endosteal(TM) (rh-endostatin, YH-16) combined with docetaxel and carboplatin (TP) regimen for the adjuvant treatment of non-small lung cancer (NSCLC) and its impact on circulating blood markers.

Methods: 36 patients with stage Ib-IIIa postoperative NSCLC, were randomly divided into the treatment group, Endosteal(TM) plus TP regimen, and the control group, TP regimen only, respectively. DFS and toxicities of patients were observed.