CAX-INTERACTING PROTEIN4 depletion causes early lethality and pre-mRNA missplicing in Arabidopsis.

Zinc knuckle (ZCCHC) motif-containing proteins are present in unicellular and multicellular eukaryotes, and most ZCCHC proteins with known functions participate in the metabolism of various classes of RNA, such as mRNAs, ribosomal RNAs, and microRNAs. The Arabidopsis (Arabidopsis thaliana) genome encodes 69 ZCCHC-containing proteins; however, the functions of most remain unclear. One of these proteins, CAX-INTERACTING PROTEIN 4 (CXIP4, encoded by AT2G28910), has been classified as a PTHR31437 family member.

CXIP4 depletion causes early lethality and pre-mRNA missplicing in Arabidopsis.

Zinc knuckle (ZCCHC) motif-containing proteins are present in unicellular and multicellular eukaryotes and most ZCCHC proteins with known functions participate in the metabolism of various classes of RNA, such as mRNAs, ribosomal RNAs, and microRNAs. The Arabidopsis () genome encodes 69 ZCCHC-containing proteins, but the functions of most remain unclear. One of these proteins is CAX-INTERACTING PROTEIN 4 (CXIP4), which has been classified as a PTHR31437 family member, along with human SREK1-interacting protein 1 (SREK1IP1), which is thought to function in pre-mRNA splicing and RNA methylation.

Circulating miRNA-21 is an innovative biomarker for cardiovascular events in erectile dysfunction patients.

Introduction: It is well-known that circulating microRNAs (miRNAs) play a relevant role in many kinds of diseases by regulating the expression of genes involved in various pathophysiologic processes, including erectile dysfunction (ED) and cardiovascular diseases (CVD).

Purpose: This study aimed to identify the miRNA-21 profile in the blood samples of patients with ED, CVD, and the combination of both pathologies to elucidate the potential function of miRNA-21.

Methods: A total of 45 patients with CVD and/or who underwent the erectile function test were included and divided into the following categories: CVD with ED (cases, = 29) and controls (= 16) with either ED or CVD.

Tomato POLLEN DEFICIENT 2 encodes a G-type lectin receptor kinase required for viable pollen grain formation.

Pollen development is a crucial biological process indispensable for seed set in flowering plants and for successful crop breeding. However, little is known about the molecular mechanisms regulating pollen development in crop species. This study reports a novel male-sterile tomato mutant, pollen deficient 2 (pod2), characterized by the production of non-viable pollen grains and resulting in the development of small parthenocarpic fruits.

Missplicing suppressor alleles of Arabidopsis PRE-MRNA PROCESSING FACTOR 8 increase splicing fidelity by reducing the use of novel splice sites.

Efficient splicing requires a balance between high-fidelity splice-site (SS) selection and speed. In Saccharomyces cerevisiae, Pre-mRNA processing factor 8 (Prp8) helps to balance precise SS selection and rapid, efficient intron excision and exon joining. argonaute1-52 (ago1-52) and incurvata13 (icu13) are hypomorphic alleles of the Arabidopsis thaliana genes ARGONAUTE1 (AGO1) and AUXIN RESISTANT6 (AXR6) that harbor point mutations creating a novel 3'SS and 5'SS, respectively.

Tomato CRABS CLAW paralogues interact with chromatin remodelling factors to mediate carpel development and floral determinacy.

CRABS CLAW (CRC) orthologues play a crucial role in floral meristem (FM) determinacy and gynoecium formation across angiosperms, the key developmental processes for ensuring successful plant reproduction and crop production. However, the mechanisms behind CRC mediated FM termination are far from fully understood. Here, we addressed the functional characterization of tomato (Solanum lycopersicum) paralogous CRC genes.

The Tomato Gene Is Required for Plant Survival Through the Proper Development of Chloroplast Thylakoid Membrane.

Since membranes play essential roles in all living beings, all cells have developed mechanisms for efficient and fast repair of membrane damage. In , the Phage shock stress A (PspA) protein is involved in the maintenance of the integrity of its inner membrane in response to the damage produced by exposure to stress conditions. A role in thylakoid membrane maintenance and reorganization has been proposed for Vesicle Inducing Protein in Plastid 1 (VIPP1), the putative PspA ortholog in .

SMALL ORGAN4 Is a Ribosome Biogenesis Factor Involved in 5.8S Ribosomal RNA Maturation.

Ribosome biogenesis is crucial for cellular metabolism and has important implications for disease and aging. Human () glioma tumor-suppressor candidate region gene2 (GLTSCR2) and yeast () Nucleolar protein53 (Nop53) are orthologous proteins with demonstrated roles as ribosome biogenesis factors; knockdown of GLTSCR2 impairs maturation of 18S and 5.8S ribosomal RNAs (rRNAs), and Nop53 is required for maturation of 5.

Genome-wide analysis of CCHC-type zinc finger (ZCCHC) proteins in yeast, Arabidopsis, and humans.

The diverse eukaryotic proteins that contain zinc fingers participate in many aspects of nucleic acid metabolism, from DNA transcription to RNA degradation, post-transcriptional gene silencing, and small RNA biogenesis. These proteins can be classified into at least 30 types based on structure. In this review, we focus on the CCHC-type zinc fingers (ZCCHC), which contain an 18-residue domain with the CXCXHXC sequence, where C is cysteine, H is histidine, and X is any amino acid.

Arabidopsis RIBOSOMAL RNA PROCESSING7 Is Required for 18S rRNA Maturation.

Ribosome biogenesis is fundamental to growth and development in eukaryotes and is linked to human diseases and cancer. MORPHOLOGY OF ARGONAUTE1-52 SUPPRESSED 2 (MAS2) participates in splicing and 45S ribosomal DNA (rDNA) expression. In a screen for MAS2 interactors, we identified RIBOSOMAL RNA PROCESSING 7 (RRP7), an ortholog of yeast rRNA processing protein 7 (Rrp7), which is required for 18S ribosomal RNA (rRNA) maturation.

Arabidopsis INCURVATA2 Regulates Salicylic Acid and Abscisic Acid Signaling, and Oxidative Stress Responses.

Epigenetic regulatory states can persist through mitosis and meiosis, but the connection between chromatin structure and DNA replication remains unclear. Arabidopsis INCURVATA2 (ICU2) encodes the catalytic subunit of DNA polymerase α, and null alleles of ICU2 have an embryo-lethal phenotype. Analysis of icu2-1, a hypomorphic allele of ICU2, demonstrated that ICU2 functions in chromatin-mediated cellular memory; icu2-1 strongly impairs ICU2 function in the maintenance of repressive epigenetic marks but does not seem to affect ICU2 polymerase activity.

Arabidopsis MAS2, an Essential Gene That Encodes a Homolog of Animal NF-κ B Activating Protein, Is Involved in 45S Ribosomal DNA Silencing.

Ribosome biogenesis requires stoichiometric amounts of ribosomal proteins and rRNAs. Synthesis of rRNAs consumes most of the transcriptional activity of eukaryotic cells, but its regulation remains largely unclear in plants. We conducted a screen for ethyl methanesulfonate-induced suppressors of Arabidopsis thaliana ago1-52, a hypomorphic allele of AGO1 (ARGONAUTE1), a key gene in microRNA pathways.

A genetic screen for suppressors of a hypomorphic allele of Arabidopsis ARGONAUTE1.

ARGONAUTE1 (AGO1) encodes a key component of the complexes mediating microRNA (miRNA) function in Arabidopsis. To study the regulation, action and interactions of AGO1, we conducted a genetic screen to identify second-site mutations modifying the morphological phenotype of ago1-52, a partial loss-of-function allele of AGO1. Unlike null ago1 mutations, the hypomorphic ago1-52 allele does not cause lethality or sterility; however, ago1-52 does produce a morphological phenotype clearly distinct from wild type.

Mutation of an Arabidopsis NatB N-alpha-terminal acetylation complex component causes pleiotropic developmental defects.

N-α-terminal acetylation is one of the most common, but least understood modifications of eukaryotic proteins. Although a high degree of conservation exists between the N-α-terminal acetylomes of plants and animals, very little information is available on this modification in plants. In yeast and humans, N-α-acetyltransferase complexes include a single catalytic subunit and one or two auxiliary subunits.

Arabidopsis TRANSCURVATA1 encodes NUP58, a component of the nucleopore central channel.

The selective trafficking of proteins and RNAs through the nuclear envelope regulates nuclear-cytoplasmic segregation of macromolecules and is mediated by nucleopore complexes (NPCs), which consist of about 400 nucleoporins (Nups) of about 30 types. Extensive studies of nucleoporin function in yeast and vertebrates showed that Nups function in nucleocytoplasmic trafficking and other processes. However, limited studies of plant Nups have identified only a few mutations, which cause pleiotropic phenotypes including reduced growth and early flowering.