Although several long noncoding RNAs (lncRNAs) have recently been shown to encode small polypeptides, those in testis remain largely uncharacterized. Here we identify two sperm-specific polypeptides, ...Kastor and Polluks, encoded by a single mouse locus (Gm9999) previously annotated as encoding a lncRNA. Both Kastor and Polluks are inserted in the outer mitochondrial membrane and directly interact with voltage-dependent anion channel (VDAC), despite their different amino acid sequences. Male VDAC3-deficient mice are infertile as a result of reduced sperm motility due to an abnormal mitochondrial sheath in spermatozoa, and deficiency of both Kastor and Polluks also severely impaired male fertility in association with formation of a similarly abnormal mitochondrial sheath. Spermatozoa lacking either Kastor or Polluks partially recapitulate the phenotype of those lacking both. Cooperative function of Kastor and Polluks in regulation of VDAC3 may thus be essential for mitochondrial sheath formation in spermatozoa and for male fertility.
Although several ribosomal protein paralogs are expressed in a tissue-specific manner, how these proteins affect translation and why they are required only in certain tissues have remained unclear. ...Here we show that RPL3L, a paralog of RPL3 specifically expressed in heart and skeletal muscle, influences translation elongation dynamics. Deficiency of RPL3L-containing ribosomes in RPL3L knockout male mice resulted in impaired cardiac contractility. Ribosome occupancy at mRNA codons was found to be altered in the RPL3L-deficient heart, and the changes were negatively correlated with those observed in myoblasts overexpressing RPL3L. RPL3L-containing ribosomes were less prone to collisions compared with RPL3-containing canonical ribosomes. Although the loss of RPL3L-containing ribosomes altered translation elongation dynamics for the entire transcriptome, its effects were most pronounced for transcripts related to cardiac muscle contraction and dilated cardiomyopathy, with the abundance of the encoded proteins being correspondingly decreased. Our results provide further insight into the mechanisms and physiological relevance of tissue-specific translational regulation.
Although long noncoding RNAs (lncRNAs) are transcripts that do not encode proteins by definition, some lncRNAs actually contain small open reading frames that are translated. TINCR (terminal ...differentiation–induced ncRNA) has been recognized as a lncRNA that contributes to keratinocyte differentiation. However, we here show that TINCR encodes a ubiquitin-like protein that is well conserved among species and whose expression was confirmed by the generation of mice harboring a FLAG epitope tag sequence in the endogenous open reading frame as well as by targeted proteomics. Forced expression of this protein promoted cell cycle progression in normal human epidermal keratinocytes, and mice lacking this protein manifested a delay in skin wound healing associated with attenuated cell cycle progression in keratinocytes. We termed this protein TINCR-encoded ubiquitin-like protein (TUBL), and our results reveal a role for TINCR in the regulation of keratinocyte proliferation and skin regeneration that is dependent on TUBL.
Translation initiates when the eIF4F complex binds the 5′ mRNA cap, followed by 5′ untranslated region scanning for the start codon by scanning ribosomes. Here, we demonstrate that the ASC‐1 complex ...(ASCC), which was previously shown to promote the dissociation of colliding 80S ribosomes, associates with scanning ribosomes to regulate translation initiation. Selective translation complex profiling (TCP‐seq) analysis revealed that ASCC3, a helicase domain‐containing subunit of ASCC, localizes predominantly to the 5′ untranslated region of mRNAs. Ribo‐seq, TCP‐seq, and luciferase reporter analyses showed that ASCC3 knockdown impairs 43S preinitiation complex loading and scanning dynamics, thereby reducing translation efficiency. Whereas eIF4A, an RNA helicase in the eIF4F complex, is important for global translation, ASCC was found to regulate the scanning process for a specific subset of transcripts. Our results have thus revealed that ASCC is required not only for dissociation of colliding 80S ribosomes but also for efficient translation initiation by scanning ribosomes at a subset of transcripts.
Synopsis
The ASC‐1 complex (ASCC) was shown to dissociate colliding 80S ribosomes. This study shows that ASCC also associates with scanning ribosomes, which is required for efficient translation initiation by scanning ribosomes at a subset of transcripts.
ASCC associates with the scanning ribosomes.
ASCC localizes predominantly to the 5′ untranslated region of mRNAs.
Loss of ASCC3 impairs preinitiation complex loading and scanning dynamics and thereby reduces translation efficiency.
Whereas eIF4A is important for global translation, ASCC regulates the scanning process for a subset of transcripts.
Different from RNA helicase eIF4A that globally controls translation initiation, the ASC‐1 complex regulates start codon scanning for a specific subset of transcripts.
Although long noncoding RNAs (lncRNAs) are transcripts that do not encode proteins by definition, some lncRNAs actually contain small open reading frames that are translated. TINCR (terminal ...differentiation–induced ncRNA) has been recognized as a lncRNA that contributes to keratinocyte differentiation. However, we here show that TINCR encodes a ubiquitin-like protein that is well conserved among species and whose expression was confirmed by the generation of mice harboring a FLAG epitope tag sequence in the endogenous open reading frame as well as by targeted proteomics. Forced expression of this protein promoted cell cycle progression in normal human epidermal keratinocytes, and mice lacking this protein manifested a delay in skin wound healing associated with attenuated cell cycle progression in keratinocytes. We termed this protein TINCR-encoded ubiquitin-like protein (TUBL), and our results reveal a role for TINCR in the regulation of keratinocyte proliferation and skin regeneration that is dependent on TUBL. Author summary Although, by definition, long noncoding RNAs (lncRNAs) are transcripts that do not encode proteins, recent studies have shown that some lncRNAs actually contain small open reading frames (ORFs) that are translated. Although TINCR (terminal differentiation–induced ncRNA) was originally identified as a lncRNA that contributes to keratinocyte differentiation, recent mass spectrometry–based analysis has suggested that TINCR is translated. Translation of the ORF within the TINCR lncRNA was validated by generating mice that harbor an in-frame insertion of the FLAG epitope tag sequence at the COOH-terminus of the ORF. The TINCR-encoded protein contains a ubiquitin-like (Ubl) domain and was designated TUBL (TINCR-encoded ubiquitin-like protein). TUBL accelerated cell cycle progression in keratinocytes, and TUBL-deficient mice manifested delayed wound healing after injury with a biopsy punch as a result of attenuated keratinocyte proliferation. TUBL plays a key role at the protein level in the maintenance of skin homeostasis after injury through promotion of keratinocyte proliferation.
Ionizing radiation is a risk factor for myeloid neoplasms including myelodysplastic syndromes (MDS), and atomic bomb survivors have been shown to have a significantly higher risk of MDS. Our previous ...analyses demonstrated that MDS among these survivors had a significantly higher frequency of complex karyotypes and structural alterations of chromosomes 3, 8, and 11. However, there was no difference in the median survival time between MDS among survivors compared with those of
origin. This suggested that a different pathophysiology may underlie the causative genetic aberrations for those among survivors. In this study, we performed genome analyses of MDS among survivors and found that proximally exposed patients had significantly fewer mutations in genes such as
along the DNA methylation pathways, and they had a significantly higher rate of 11q deletions. Among the genes located in the deleted portion of chromosome 11, alterations of
were significantly more frequent in proximally exposed group with mutations identified on the remaining allele in 2 out of 5 cases.
, which is frequently mutated in therapy-related myeloid neoplasms, was equally affected between proximally and distally exposed patients. These results suggested that the genetic aberration profiles in MDS among atomic bomb survivors differed from those in therapy-related and
origin. Considering the role of
in DNA damage response after radiation exposure, further studies are warranted to elucidate how 11q deletion and aberrations of
contribute to the pathogenesis of MDS after radiation exposure.
•Nutritional support during allogeneic hematopoietic stem cell transplantation results in better clinical outcomes.•Early nutritional support improves the gut microbiome environment after allogeneic ...hematopoietic stem cell transplantation.•Nutritional support was found to greatly affect the onset of intestinal graft-versus-host disease.•Microbial diversity was correlated with the nutritional status.
Intensive nutritional support during allogeneic hematopoietic stem cell transplantation (allo-HSCT) yields improved clinical outcomes. However, the clinical implications of early enteral nutrition (EN) in allo-HSCT remain unclear. This retrospective study was conducted to determine the significance of early EN in individuals who underwent allo-HSCT, and the association between early nutritional intervention and clinical outcomes, including the status of the intestinal microbiome.
Thirty-one participants received EN before conditioning. The intestinal microbiota was examined by meta 16S rRNA gene sequencing of fecal samples.
The median body mass variation was only −0.35 kg on day 60. The probability of 2-y overall survival was 61.1%. The cumulative incidence of treatment-related mortality was 17.4%, and those of acute graft-versus-host disease were 32.3% (grades II–IV) and 3.2% (grades III–IV). Chronic graft-versus-host disease was observed in four participants. Dysbiosis of the intestines and acute graft-versus-host disease occurred simultaneously, and Enterococcus species were abundant.
Our results suggest that early nutritional support can improve the outcomes for individuals who have undergone allo-HSCT and can maintain homeostasis of their intestinal microbiome. Future prospective clinical trials are required to elucidate the role of EN in allo-HSCT and the association between the intestinal microbiome and EN.
An improved synthesis of the highly selective EP4-receptor agonist ONO-4819 has been developed. The previous synthesis suffered from several drawbacks, in which a critical one is the difficulty in ...the removal of byproducts leading to unsatisfactory quality of the active pharmaceutical ingredient (API). Furthermore, on stereoselective reduction of an enone intermediate by binaphthol-modified lithium aluminum hydride, low concentration of the reaction conditions and tedious purification procedures to remove excess binaphthol were critical issues for the manufacturing process of the API. In the improved process, we have developed improved conditions using γ-thiobutyrolactone as sulfur source instead of potassium thioacetate to introduce the sulfur-containing C4 side chain without formation of byproducts. For stereoselective synthesis of the chiral alcohol, (−)-DIP-chloride reduction is found to be the best method, which can improve not only the enantioselectivity but also the workload for removing the chiral modifier in a purification process. Furthermore, benzoyl and tert-butyldimethylsilyl groups as protecting groups for hydroxyl functions were used for precise process controls of all intermediates. By changing these protecting groups, the purity of ONO-4819 was strictly controlled through crystalline intermediates. Thus, an improved robust process for ONO-4819 with a high chemical purity was developed.
The alcohol 2, a key intermediate in the synthesis of the highly selective EP4-receptor agonist ONO-4819, was synthesized by (R)-methyloxazaborolidine ((R)-Me-CBS)-catalyzed asymmetric reduction of ...enone 1 with borane dimethylsulfide complex. Addition of water and phenol to the reduction of enone 1 using (R)-Me-CBS as catalyst changed the chemoselectivity of the reduction.
PDF
