TSP1 is the essential domain of SEMA5A involved in pannus formation in rheumatoid arthritis

Objective In this study, we explored the effect of semaphorin5A (SEMA5A) on rheumatoid arthritis (RA) pathogenesis and its specific TSP1 domain on pannus formation. Methods The expression of SEMA5A was detected in synovium, fibroblast-like synoviocytes (FLS) and synovial fluid of RA patients and healthy controls (HCs) by q-PCR, IHC, WB and ELISA. SEMA5A-mAb intervention was performed to appraise the severity of joints in CIA model. Transcriptome sequencing and bioinformatics analysis in SEMA5A transfected FLS from HCs were performed to screen differentially expressed genes after SEMA5A overexpression. MTT assay in RA-FLS, chicken embryo allantoic membrane experiment and tube formation experiment were used to clarify the influence of SEMA5A on cell proliferation and angiogenesis. Furthermore, rescue experiment verified the function of TSP1 domain of SEMA5A in the progress of RA with Sema5a-/- CIA mice. Results The expression of SEMA5A increased in RA compared with HCs. Simultaneously, SEMA5A-mAb significantly attenuated joint injury and inflammatory response in CIA models. Besides, transcriptome sequencing and angiogenesis-related experiments verified the ability of SEMA5A to promote FLS proliferation and angiogenesis. Moreover, TSP1 was proved as an essential domain in SEMA5A-inducing angiogenesis in vitro. Additionally, rescue of TSP1-deleted SEMA5A failed to deteriorate the severity of arthritis in CIA model constructed with Sema5a -/- mice. Conclusions In summary, up-regulation of SEMA5A was firstly confirmed in pathological lesion of RA patients. Furthermore, the treatment of SEMA5A-mAb attenuated the progress of RA in CIA model. Moreover, TSP1 was indicated as the key domain of SEMA5A to promote pannus formation in RA.

Contractions of the C-Terminal Domain of Saccharomyces cerevisiae Rpb1p Are Mediated by Rad5p

The C-terminal domain (CTD) is an essential domain of the largest subunit of RNA polymerase II, Rpb1p, and is composed of 26 tandem repeats of a seven-amino acid sequence, YSPTSPS. Despite being an essential domain within an essential gene, we have previously demonstrated that the CTD coding region is genetically unstable. Furthermore, yeast with a truncated or mutated CTD sequence are capable of promoting spontaneous genetic expansion or contraction of this coding region to improve fitness. We investigated the mechanism by which the CTD contracts using a tet-off reporter system for RPB1 to monitor genetic instability within the CTD coding region. We report that contractions require the post-replication repair factor Rad5p but, unlike expansions, not the homologous recombination factors Rad51p and Rad52p. Sequence analysis of contraction events reveals that deleted regions are flanked by microhomologies. We also find that G-quadruplex forming sequences predicted by the QGRS Mapper are enriched on the noncoding strand of the CTD compared to the body of RPB1. Formation of G-quadruplexes in the CTD coding region could block the replication fork, necessitating post-replication repair. We propose that contractions of the CTD result when microhomologies misalign during Rad5p-dependent template switching via fork reversal.

Template Switching Mediates Contractions of a Repetitive Coding Region in S. cerevisiae

ABSTRACTThe C-terminal domain (CTD) is an essential domain of the largest subunit of RNA polymerase II, Rpb1p, and is composed of 26 tandem repeats of a seven-amino acid sequence, YSPTSPS. Despite being an essential domain within an essential gene, we have previously demonstrated that the CTD coding region is genetically unstable. Furthermore, yeast with a truncated or mutated CTD sequence are capable of promoting spontaneous genetic expansion or contraction of this coding region to improve fitness. We investigated the mechanism by which the CTD contracts using a tet-off reporter system for RPB1 to monitor genetic instability within the CTD coding region. We report that contractions require the post-replication repair factor Rad5p but, unlike expansions, not the homologous recombination factors Rad51p and Rad52p. Sequence analysis of contraction events reveals that deleted regions are flanked by microhomologies. We also find that G-quadruplex forming sequences predicted by the QGRS Mapper are enriched on the noncoding strand of the CTD compared to the body of RPB1. Formation of G-quadruplexes in the CTD coding region could block the replication fork, necessitating post-replication repair by template switching. We propose that contractions of the CTD result when microhomologies misalign during Rad5p-dependent template switching via fork reversal.

Identification of Delay Causing Actor in the Indian Real Estate Project: an AHP-Based Approach

Indian construction is a vital domain with an enormous employment potential and its contribution to the economy. Real estate is an essential domain of construction that tackles the housing demands. In the present scenario, this sector is experiencing a slowdown often failing projects. Thus, the aim is to identify the project participant and attributes that lead to delays in the schedule of real estate projects. In this process, we apply the hierarchical analytical process to identify the actor and the causes that result in an overrun. Our findings suggest that to a significant extent delays occur due to contractors under the influence of distinct factors discussed in the study.