Molecular and Cellular Events in Early Thymocyte Development 11Received for publication October 14, 1997

The field of molecular biology has provided great insights into the structure and function of key molecules. Thanks to this area of research, we can now grasp the biological details of DNA and have characterised an enormous number of molecules in massive data bases. These 'biological periodic tables' have allowed scientists to connect molecules to particular cellular events, furthering scientific understanding of biological processes. However, molecular biology has yet to answer questions regarding 'higher-order' molecular architecture, such as that of chromatin. Chromatin is the molecular material that serves as the building block for chromosomes, the structures that carry an organism's genetic information inside of the cell's nucleus. Understanding the physical properties of chromatin is crucial in developing a more thorough picture of how chromatin's structure relate to its key cellular functions. Moreover, by establishing a physical model of chromatin, scientists will be able to open the doors into the true inner workings of the cell nucleus. Professor Shin-ichi Tate and his team of researchers at Hiroshima University's Research Center for the Mathematics on Chromatin Live Dynamics (RcMcD), are attempting to do just that. Through a five-year grant funded by the Platform for Dynamic Approaches to Living Systems from the Ministry of Education, Culture, Sports, Science and Technology, Tate is aiming to gain a clearer understanding of the structure and dynamics of chromatin.

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Roles of pRB in the Regulation of Nucleosome and Chromatin Structures

BioMed Research International ◽

10.1155/2016/5959721 ◽

2016 ◽

Vol 2016 ◽

pp. 1-11 ◽

Cited By ~ 10

Author(s):

Chiharu Uchida

Keyword(s):

Target Genes ◽

Chromosome Instability ◽

Cancer Therapies ◽

Induce Cell Cycle Arrest ◽

Cellular Events ◽

Cycle Arrest ◽

Histone Modifiers ◽

Physical Interactions ◽

Functional Inactivation

Retinoblastoma protein (pRB) interacts with E2F and other protein factors to play a pivotal role in regulating the expression of target genes that induce cell cycle arrest, apoptosis, and differentiation. pRB controls the local promoter activity and has the ability to change the structure of nucleosomes and/or chromosomes via histone modification, epigenetic changes, chromatin remodeling, and chromosome organization. Functional inactivation of pRB perturbs these cellular events and causes dysregulated cell growth and chromosome instability, which are hallmarks of cancer cells. The role of pRB in regulation of nucleosome/chromatin structures has been shown to link to tumor suppression. This review focuses on the ability of pRB to control nucleosome/chromatin structures via physical interactions with histone modifiers and chromatin factors and describes cancer therapies based on targeting these protein factors.

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Adiponectin: Structure, Physiological Functions, Role in Diseases, and Effects of Nutrition

Nutrients ◽

10.3390/nu13041180 ◽

2021 ◽

Vol 13 (4) ◽

pp. 1180

Author(s):

Kayvan Khoramipour ◽

Karim Chamari ◽

Amirhosein Ahmadi Hekmatikar ◽

Amirhosein Ziyaiyan ◽

Shima Taherkhani ◽

...

Keyword(s):

Cardiovascular Disease ◽

Amino Acids ◽

Molecular Weight ◽

Energy Regulation ◽

Treatment Interventions ◽

Adipose Tissues ◽

Physiological Functions ◽

Cellular Events ◽

Healthy Nutrition

Adiponectin (a protein consisting of 244 amino acids and characterized by a molecular weight of 28 kDa) is a cytokine that is secreted from adipose tissues (adipokine). Available evidence suggests that adiponectin is involved in a variety of physiological functions, molecular and cellular events, including lipid metabolism, energy regulation, immune response and inflammation, and insulin sensitivity. It has a protective effect on neurons and neural stem cells. Adiponectin levels have been reported to be negatively correlated with cancer, cardiovascular disease, and diabetes, and shown to be affected (i.e., significantly increased) by proper healthy nutrition. The present review comprehensively overviews the role of adiponectin in a range of diseases, showing that it can be used as a biomarker for diagnosing these disorders as well as a target for monitoring the effectiveness of preventive and treatment interventions.

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OMIP 073: Analysis of human thymocyte development with a 14‐color flow cytometry panel

Cytometry Part A ◽

10.1002/cyto.a.24326 ◽

2021 ◽

Author(s):

Sarah‐Jolan Bremer ◽

Laura Glau ◽

Christina Gehbauer ◽

Annika Boxnick ◽

Daniel Biermann ◽

...

Keyword(s):

Flow Cytometry ◽

Thymocyte Development ◽

Color Flow ◽

Human Thymocyte

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CD45-null transgenic mice reveal a positive regulatory role for CD45 in early thymocyte development, in the selection of CD4+CD8+ thymocytes, and B cell maturation.

Journal of Experimental Medicine ◽

10.1084/jem.183.4.1707 ◽

1996 ◽

Vol 183 (4) ◽

pp. 1707-1718 ◽

Cited By ~ 269

Author(s):

K F Byth ◽

L A Conroy ◽

S Howlett ◽

A J Smith ◽

J May ◽

...

Keyword(s):

Signal Transduction ◽

T Cell ◽

B Cells ◽

Transgenic Mice ◽

B Cell ◽

T Cell Development ◽

Cell Development ◽

Cross Linking ◽

Thymocyte Development ◽

Double Positive

The CD45 transmembrane glycoprotein has been shown to be a protein phosphotyrosine phosphatase and to be important in signal transduction in T and B lymphocytes. We have employed gene targeting to create a strain of transgenic mice that completely lacks expression of all isoforms of CD45. The spleens from CD45-null mice contain approximately twice the number of B cells and one fifth the number of T cells found in normal controls. The increase in B cell numbers is due to the specific expansion of two B cell subpopulations that express high levels of immunoglobulin (IgM) staining. T cell development is significantly inhibited in CD45-null animals at two distinct stages. The efficiency of the development of CD4-CD8- thymocytes into CD4+ CD8+ thymocytes is reduced by twofold, subsequently the frequency of successful maturation of the double positive population into mature, single positive thymocytes is reduced by a further four- to fivefold. In addition, we demonstrate that CD45-null thymocytes are severely impaired in their apoptotic response to cross-linking signals via T cell receptor (TCR) in fetal thymic organ culture. In contrast, apoptosis can be induced normally in CD45-null thymocytes by non-TCR-mediated signals. Since both positive and negative selection require signals through the TCR complex, these findings suggest that CD45 is an important regulator of signal transduction via the TCR complex at multiple stages of T cell development. CD45 is absolutely required for the transmission of mitogenic signals via IgM and IgD. By contrast, CD45-null B cells proliferate as well as wild-type cells to CD40-mediated signals. The proliferation of B cells in response to CD38 cross-linking is significantly reduced but not abolished by the CD45-null mutation. We conclude that CD45 is not required at any stage during the generation of mature peripheral B cells, however its loss reveals a previously unrecognized role for CD45 in the regulation of certain subpopulations of B cells.

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