Effect of heterozygous deletions on phenotypic changes and dosage compensation in Arabidopsis thaliana.

Heterozygous deletions, which include a large number of genes, are often caused by the induction of mutations. The induction of gene dosage compensation should be considered when assessing the effects of heterozygous deletions on phenotypic changes. This mechanism is known to balance the expression levels of genes with different copy numbers in sex chromosomes, but it is also known to operate in autosomes.

Rare occurrence of cryptic 5' splice sites by downstream 3' splice site/exon boundary mutations in a heavy-ion-induced allele of .

Pre-mRNA splicing is a fundamental process in eukaryotic gene expression, and the mechanism of intron definition, involving the recognition of the canonical GU (5'-splice site) and AG (3'-splice site) dinucleotides by splicing factors, has been postulated for most cases of splicing initiation in plants. Splice site mutations have played crucial roles in unraveling the mechanism of pre-mRNA splicing . Typically, splice site mutations abolish splicing events or activate one or more cryptic splice sites surrounding the mutated region.

Sex chromosome cycle as a mechanism of stable sex determination.

Recent advances in DNA sequencing technology have enabled the precise decoding of genomes in non-model organisms, providing a basis for unraveling the patterns and mechanisms of sex chromosome evolution. Studies of different species have yielded conflicting results regarding the traditional theory that sex chromosomes evolve from autosomes via the accumulation of deleterious mutations and degeneration of the Y (or W) chromosome. The concept of the 'sex chromosome cycle,' emerging from this context, posits that at any stage of the cycle (i.

Principles of amyloplast replication in the ovule integuments of Arabidopsis thaliana.

Plastids in vascular plants have various differentiated forms, among which amyloplasts are crucial for starch storage and plant productivity. Despite the vast knowledge of the binary-fission mode of chloroplast division, our understanding of the replication of non-photosynthetic plastids, including amyloplasts, remains limited. Recent studies have suggested the involvement of stromules (stroma-filled tubules) in plastid replication when the division apparatus is faulty.

Genomic view of heavy-ion-induced deletions associated with distribution of essential genes in .

Heavy-ion beam, a type of ionizing radiation, has been applied to plant breeding as a powerful mutagen and is a promising tool to induce large deletions and chromosomal rearrangements. The effectiveness of heavy-ion irradiation can be explained by linear energy transfer (LET; keV µm). Heavy-ion beams with different LET values induce different types and sizes of mutations.

Evolution of sex-determination in dioecious plants: From active Y to X/A balance?

Sex chromosomes in plants have been known for a century, but only recently have we begun to understand the mechanisms behind sex determination in dioecious plants. Here, we discuss evolution of sex determination, focusing on Silene latifolia, where evolution of separate sexes is consistent with the classic "two mutations" model-a loss of function male sterility mutation and a gain of function gynoecium suppression mutation, which turned an ancestral hermaphroditic population into separate males and females. Interestingly, the gynoecium suppression function in S.

The origin and evolution of sex chromosomes, revealed by sequencing of the Silene latifolia female genome.

White campion (Silene latifolia, Caryophyllaceae) was the first vascular plant where sex chromosomes were discovered. This species is a classic model for studies on plant sex chromosomes due to presence of large, clearly distinguishable X and Y chromosomes that originated de novo about 11 million years ago (mya), but lack of genomic resources for this relatively large genome (∼2.8 Gb) remains a significant hurdle.

A CLAVATA3-like Gene Acts as a Gynoecium Suppression Function in White Campion.

How do separate sexes originate and evolve? Plants provide many opportunities to address this question as they have diverse mating systems and separate sexes (dioecy) that evolved many times independently. The classic "two-factor" model for evolution of separate sexes proposes that males and females can evolve from hermaphrodites via the spread of male and female sterility mutations that turn hermaphrodites into females and males, respectively. This widely accepted model was inspired by early genetic work in dioecious white campion (Silene latifolia) that revealed the presence of two sex-determining factors on the Y-chromosome, though the actual genes remained unknown.

Femoral Valgus Correction Angle for the Intramedullary Alignment Rod Is Strongly Associated with Femoral Lateral Bowing in Japanese Patients with Varus Knee Osteoarthritis Undergoing Total Knee Arthroplasty.

Background: This study aimed to investigate factors, such as differences in femoral shape, that could affect the femoral valgus correction angle (VCA) for the intramedullary alignment rod (IM rod) by using a three-dimensional (3D) measurement system in patients with varus knee osteoarthritis undergoing total knee arthroplasty (TKA).

Methods: A total of 305 knees in 233 Japanese patients with varus knee osteoarthritis who underwent primary TKA by using Jig Engaged 3D Pre-Operative Planning Software for the TKA operation support system was examined. We retrospectively analysed factors, such as the shape of the proximal, middle, and distal femur in the coronal plane, all of which could affect the VCA for the IM rod, by multiple linear regression analyses.

Double Mutant Analysis with the Large Flower Mutant, , to Explore the Regulatory Network Controlling the Flower and Seed Sizes in .

Two growth processes, cell proliferation and expansion, determine plant species-specific organ sizes. A large flower mutant in , (), was isolated from a mutant library. In the flowers, post-mitotic cell expansion and endoreduplication of nuclear DNA were promoted.

Arterial embolism due to massive cement leakage during total hip arthroplasty revision.

Total hip arthroplasty with cementing techniques leads to good clinical outcomes, but critical vascular complications can sometimes occur due to cement leakage into the pelvis. In this report, we describe a case of massive cement leakage that caused an arterial embolism. When exfoliating cement from an artery, the surgeon should note not only direct injury to the vessels but also the potential for arterial embolism.

An Argon-Ion-Induced Pale Green Mutant of Exhibiting Rapid Disassembly of Mesophyll Chloroplast Grana.

Argon-ion beam is an effective mutagen capable of inducing a variety of mutation types. In this study, an argon ion-induced pale green mutant of was isolated and characterized. The mutant, designated Ar50-33-pg1, exhibited moderate defects of growth and greening and exhibited rapid chlorosis in photosynthetic tissues.

TGD5 is required for normal morphogenesis of non-mesophyll plastids, but not mesophyll chloroplasts, in Arabidopsis.

Stromules are dynamic membrane-bound tubular structures that emanate from plastids. Stromule formation is triggered in response to various stresses and during plant development, suggesting that stromules may have physiological and developmental roles in these processes. Despite the possible biological importance of stromules and their prevalence in green plants, their exact roles and formation mechanisms remain unclear.

Evaluation of an operation support system using the femoral anterior tangent line to determine intraoperative femoral component rotation in total knee arthroplasty.

Background: The femoral anterior tangent (FAT) line refers to a line parallel to the anterior surface of the distal femur in the axial plane. This study aimed to evaluate the effectiveness of a new operation support system which uses the FAT line to set the femoral component rotational alignment in total knee arthroplasty (TKA).

Methods: A total of 170 consecutive knees in 139 patients undergoing primary TKA with the JIGEN (Jig Engaged Three-dimensional (3D) Pre-Operative Planning Software for TKA) operation support system was examined.

A Method Enabling Comprehensive Isolation of Arabidopsis Mutants Exhibiting Unusual Root Mechanical Behavior.

Root penetration into soils is fundamental for land plants to support their own aboveground parts and forage water and nutrients. To elucidate the molecular mechanisms underlying root mechanical penetration, mutants defective in this behavior need to be comprehensively isolated; however, established methods are currently scarce. We herein report a method to screen for these mutants of and present their phenotypes.

Isolation and characterization of a motility-defective mutant of .

is a green photosynthetic microalga that swims using its flagellum. This species has been used as a model organism for over half a century to study its metabolism and the mechanisms of its behavior. The development of mass-cultivation technology has led to application as a feedstock in various products such as foods.

Sexual Difference in the Optimum Environmental Conditions for Growth and Maturation of the Brown Alga in the Gametophyte Stage.

is an annual brown kelp growing naturally in coastal areas as a major primary producer in temperate regions and is cultivated on an industrial scale. Kelps have a heteromorphic life cycle characterized by a macroscopic sporophyte and microscopic sexual gametophytes. The sex-dependent effects of different environmental factors on the growth and maturation characteristics of the gametophyte stage were investigated using response surface methodology.

An asexual flower of Silene latifolia and Microbotryum lychnidis-dioicae promotes sex-organ development.

Silene latifolia is a dioecious flowering plant with sex chromosomes in the family Caryophyllaceae. Development of a gynoecium and stamens are suppressed in the male and female flowers of S. latifolia, respectively.

Development of the VIGS System in the Dioecious Plant .

(1) Background: is a dioecious plant, whose sex is determined by XY-type sex chromosomes. is a smut fungus that infects plants and causes masculinization in female flowers, as if were acting as a sex-determining gene. Recent large-scale sequencing efforts have promised to provide candidate genes that are involved in the sex determination machinery in plants.

LET dependence on killing effect and mutagenicity in the model filamentous fungus Neurospora crassa.

Purpose: To assess the unique biological effects of different forms of ionizing radiation causing DNA double-strand breaks (DSBs), we compared the killing effect, mutagenesis frequency, and mutation type spectrum using the model filamentous fungus Neurospora.

Materials And Methods: Asexual spores of wild-type Neurospora and two DSB repair-deficient strains [one homologous recombination- and the other non-homologous end-joining (NHEJ) pathway-deficient] were irradiated with argon (Ar)-ion beams, ferrous (Fe)-ion beams, or X-rays. Relative biological effectiveness (RBE), forward mutation frequencies at the ad-3 loci, and mutation spectra at the ad-3B gene were determined.

An early-flowering einkorn wheat mutant with deletions of PHYTOCLOCK 1/LUX ARRHYTHMO and VERNALIZATION 2 exhibits a high level of VERNALIZATION 1 expression induced by vernalization.

Using heavy-ion beam mutagenesis of Triticum monococcum strain KU104-1, we identified a mutant that shows extra early-flowering; it was named extra early-flowering 3 (exe3). Here, we carried out expression analyses of clock-related genes, clock downstream genes and photoperiod pathway genes, and found that the clock component gene PHYTOCLOCK 1/LUX ARRHYTHMO (PCL1/LUX) was not expressed in exe3 mutant plants. A PCR analysis of DNA markers indicated that the exe3 mutant had a deletion of wheat PCL1/LUX (WPCL1), and that the WPCL1 deletion was correlated with the mutant phenotype in the segregation line.

Different mutational function of low- and high-linear energy transfer heavy-ion irradiation demonstrated by whole-genome resequencing of Arabidopsis mutants.

Heavy-ion irradiation is a powerful mutagen that possesses high linear energy transfer (LET). Several studies have indicated that the value of LET affects DNA lesion formation in several ways, including the efficiency and the density of double-stranded break induction along the particle path. We assumed that the mutation type can be altered by selecting an appropriate LET value.