First report of Rhnullindividuals in the Indian population and characterization of the underlying molecular mechanisms

Abstract Fiber mutants are unique and valuable resources for understanding the genetic and molecular mechanisms controlling initiation and development of cotton fibers that are extremely elongated single epidermal cells protruding from the seed coat of cottonseeds. In this study, we reported a new fuzzless-tufted cotton mutant (Gossypium hirsutum) and showed that fuzzless-tufted near-isogenic lines (NILs) had similar agronomic traits and a higher ginning efficiency compared to their recurrent parents with normal fuzzy seeds. Genetic analysis revealed that the mutant phenotype is determined by a single incomplete dominant locus, designated N5. The mutation was fine mapped to an approximately 250-kb interval containing 33 annotated genes using a combination of bulked segregant sequencing, SNP chip genotyping, and fine mapping. Comparative transcriptomic analysis using 0–6 days post-anthesis (dpa) ovules from NILs segregating for the phenotypes of fuzzless-tufted (mutant) and normal fuzzy cottonseeds (wild-type) uncovered candidate genes responsible for the mutant phenotype. It also revealed that the flanking region of the N5 locus is enriched with differentially expressed genes (DEGs) between the mutant and wild-type. Several of those DEGs are members of the gene families with demonstrated roles in cell initiation and elongation, such as calcium-dependent protein kinase and expansin. The transcriptome landscape of the mutant was significantly reprogrammed in the 6 dpa ovules and, to a less extent, in the 0 dpa ovules, but not in the 2 and 4 dpa ovules. At both 0 and 6 dpa, the reprogrammed mutant transcriptome was mainly associated with cell wall modifications and transmembrane transportation, while transcription factor activity was significantly altered in the 6 dpa mutant ovules. These results imply a similar molecular basis for initiation of lint and fuzz fibers despite certain differences.

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Identification and Characterization of Inorganic Pyrophosphatase and PAP Phosphatase from Thermococcus onnurineus NA1

Journal of Bacteriology ◽

10.1128/jb.01699-08 ◽

2009 ◽

Vol 191 (10) ◽

pp. 3415-3419 ◽

Cited By ~ 4

Author(s):

Hyun Sook Lee ◽

Yun Jae Kim ◽

Jung-Hyun Lee ◽

Sung Gyun Kang

Keyword(s):

Gene Clusters ◽

Inorganic Pyrophosphatase ◽

Thermococcus Onnurineus Na1 ◽

First Report ◽

Activation System ◽

Sulfate Activation ◽

Pyrococcus Abyssi ◽

Identification And Characterization ◽

Hypothetical Genes

ABSTRACT Two hypothetical genes were functionally verified to be a pyrophosphatase and a PAP phosphatase in Thermococcus onnurineus NA1. This is the first report of the pyrophosphatases and the PAP phosphatases being organized in the gene clusters of the sulfate activation system only in T. onnurineus NA1 and “Pyrococcus abyssi.”

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A Concerted Action of UBA5 C-Terminal Unstructured Regions Is Important for Transfer of Activated UFM1 to UFC1

International Journal of Molecular Sciences ◽

10.3390/ijms22147390 ◽

2021 ◽

Vol 22 (14) ◽

pp. 7390

Author(s):

Nicole Wesch ◽

Frank Löhr ◽

Natalia Rogova ◽

Volker Dötsch ◽

Vladimir V. Rogov

Keyword(s):

Cellular Localization ◽

Molecular Mechanisms ◽

Biochemical Characterization ◽

Effective Interaction ◽

Regulatory Region ◽

Titration Calorimetry ◽

Enzymatic Reactions ◽

Cellular Processes ◽

Mechanism Of Interaction

Ubiquitin fold modifier 1 (UFM1) is a member of the ubiquitin-like protein family. UFM1 undergoes a cascade of enzymatic reactions including activation by UBA5 (E1), transfer to UFC1 (E2) and selective conjugation to a number of target proteins via UFL1 (E3) enzymes. Despite the importance of ufmylation in a variety of cellular processes and its role in the pathogenicity of many human diseases, the molecular mechanisms of the ufmylation cascade remains unclear. In this study we focused on the biophysical and biochemical characterization of the interaction between UBA5 and UFC1. We explored the hypothesis that the unstructured C-terminal region of UBA5 serves as a regulatory region, controlling cellular localization of the elements of the ufmylation cascade and effective interaction between them. We found that the last 20 residues in UBA5 are pivotal for binding to UFC1 and can accelerate the transfer of UFM1 to UFC1. We solved the structure of a complex of UFC1 and a peptide spanning the last 20 residues of UBA5 by NMR spectroscopy. This structure in combination with additional NMR titration and isothermal titration calorimetry experiments revealed the mechanism of interaction and confirmed the importance of the C-terminal unstructured region in UBA5 for the ufmylation cascade.

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High-resolution view of HIV-1 reverse transcriptase initiation complexes and inhibition by NNRTI drugs

Nature Communications ◽

10.1038/s41467-021-22628-9 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Betty Ha ◽

Kevin P. Larsen ◽

Jingji Zhang ◽

Ziao Fu ◽

Elizabeth Montabana ◽

...

Keyword(s):

Reverse Transcriptase ◽

Viral Entry ◽

Reverse Transcription ◽

Molecular Mechanisms ◽

Dissociation Kinetics ◽

Structural Mechanism ◽

Medium Resolution ◽

Kinetics Of ◽

Hiv 1

AbstractReverse transcription of the HIV-1 viral RNA genome (vRNA) is an integral step in virus replication. Upon viral entry, HIV-1 reverse transcriptase (RT) initiates from a host tRNALys3 primer bound to the vRNA genome and is the target of key antivirals, such as non-nucleoside reverse transcriptase inhibitors (NNRTIs). Initiation proceeds slowly with discrete pausing events along the vRNA template. Despite prior medium-resolution structural characterization of reverse transcriptase initiation complexes (RTICs), higher-resolution structures of the RTIC are needed to understand the molecular mechanisms that underlie initiation. Here we report cryo-EM structures of the core RTIC, RTIC–nevirapine, and RTIC–efavirenz complexes at 2.8, 3.1, and 2.9 Å, respectively. In combination with biochemical studies, these data suggest a basis for rapid dissociation kinetics of RT from the vRNA–tRNALys3 initiation complex and reveal a specific structural mechanism of nucleic acid conformational stabilization during initiation. Finally, our results show that NNRTIs inhibit the RTIC and exacerbate discrete pausing during early reverse transcription.

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Hemolysis in the spleen drives erythrocyte turnover

Blood ◽

10.1182/blood.2020005351 ◽

2020 ◽

Author(s):

Thomas robert leon Klei ◽

Jill Jasmine Dalimot ◽

Benjamin Nota ◽

Martijn Veldthuis ◽

Erik Mul ◽

...

Keyword(s):

Molecular Mechanisms ◽

Matrix Proteins ◽

Human Spleen ◽

Erythrocyte Adhesion ◽

Subsequent Degradation ◽

Macrophage Subpopulations ◽

Senescent Erythrocytes ◽

Red Pulp

Red pulp macrophages of the spleen mediate turnover of billions of senescent erythrocytes per day. However, the molecular mechanisms involved in sequestration of senescent erythrocytes, their recognition and their subsequent degradation by red pulp macrophages remain unclear. In this study we provide evidence that the splenic environment is of substantial importance in facilitating erythrocyte turnover through induction of hemolysis. Upon isolating human spleen red pulp macrophages we noted a substantial lack of macrophages that were in the process of phagocytosing intact erythrocytes. Detailed characterization of erythrocyte and macrophage subpopulations from human spleen tissue led to the identification of erythrocytes that are devoid of hemoglobin, so-called erythrocyte ghosts. By in vivo imaging and transfusion experiments we further confirmed that senescent erythrocytes that are retained in the spleen are subject to hemolysis. Additionally, we show that erythrocyte adhesion molecules, which are specifically activated on aged erythrocytes, cause senescent erythrocytes to interact with extracellular matrix proteins that are exposed within the splenic architecture. Such adhesion molecule-driven retention of senescent erythrocytes, under low shear conditions, was found to result in steady shrinkage of the cell and ultimately resulted in hemolysis. In contrast to intact senescent erythrocytes, the remnant erythrocyte ghost shells were prone to recognition and breakdown by red pulp macrophages. These data identify hemolysis as a key event in the turnover of senescent erythrocytes, which alters our current understanding of how erythrocyte degradation is regulated.

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Further Support of Conspecificity of Oak and Mango Powdery Mildew and First Report of Erysiphe quercicola and Erysiphe alphitoides on Mango in Mainland Europe

Plant Disease ◽

10.1094/pdis-01-17-0116-re ◽

2017 ◽

Vol 101 (7) ◽

pp. 1086-1093 ◽

Cited By ~ 8

Author(s):

Marie-Laure Desprez-Loustau ◽

Marie Massot ◽

Nicolas Feau ◽

Tania Fort ◽

Antonio de Vicente ◽

...

Keyword(s):

Powdery Mildew ◽

Host Range ◽

Molecular Mechanisms ◽

Single Copy ◽

Broad Host Range ◽

First Report ◽

Erysiphe Quercicola ◽

Powdery Mildews ◽

Mango Leaves ◽

Practical Implications

Mango leaves and inflorescences infected by powdery mildew in southern Spain were analyzed using multigene sequencing (ITS + 4 single-copy coding genes) to identify the causal agent. Erysiphe quercicola was detected in 97% out of 140 samples, collected in six different orchards in the Malaga region. Among these, a small proportion also yielded E. alphitoides (8% of all samples) and E. alphitoides was found alone in 3% of samples. A phylogenetic approach was completed by cross inoculations between oak and mango, which led to typical symptoms, supporting the conspecificity of oak and mango powdery mildews. To our knowledge, this is the first report of E. quercicola and E. alphitoides causing powdery mildew on mango trees in mainland Spain, and thus mainland Europe, based on unequivocal phylogenetic and biological evidence. Our study thus confirmed the broad host range of both E. quercicola and E. alphitoides. These results have practical implications in terms of the demonstrated ability for host range expansion in powdery mildews. They also open interesting prospects to the elucidation of molecular mechanisms underlying the ability to infect single versus multiple and unrelated host plants since these two closely related powdery mildew species belong to a small clade with both generalist and specialist powdery mildews.

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