Civil Rights
Movements, leaders, victories and the continuing fight for equality.
q2K BHP
Black History Portal
THE BHP WIRE —
HIDDEN TRUTHS
What's New!
Explore the people, places, events, achievements, struggles and stories that shaped our journey.
Movements, leaders, victories and the continuing fight for equality.
Innovation, patents, science, technology and world-changing contributions.
Pioneers, champions, Negro Leagues, records, activism and excellence.
Meet the people whose lives, choices and achievements shaped the journey.
Black towns, communities, institutions and places where history happened.
Moments that changed communities, movements, institutions and the nation.
In 1968 Shirley Chisholm became the first Black woman elected to the United States Congress. In 1972 she launched a campaign for the Democratic presidential nomination, breaking another political barrier.
MORE →Reflects the personal views, recollections, and perspective of the author, Mike Davis.
This is a personal recollection on the Move fire on May 13, 1985
HLA class II histocompatibility antigen, DM beta chain is a protein that in humans is encoded by the HLA-DMB gene.
HLA-DM (human leukocyte antigen DM) is an intracellular protein involved in the mechanism of antigen presentation on antigen presenting cells (APCs) of the immune system. It does this by assisting in peptide loading of major histocompatibility complex (MHC) class II membrane-bound proteins. HLA-DM is encoded by the genes HLA-DMA and HLA-DMB. HLA-DM is a molecular chaperone that works in lysosomes and endosomes in cells of the immune system. It works in APCs like macrophages, dendritic cells, and B cells by interacting with MHC class II molecules. HLA-DM protects the MHC class II molecules from breaking down, and regulates which proteins or peptides bind to them as well. This regulates how and when a peptide acts as an antigen initiating an immune response. Thus, HLA-DM is necessary for the immune system to respond effectively to a foreign invader. Impairment in HLA-DM function can result in immunodeficiency and autoimmune diseases.
HLA class II histocompatibility antigen, DM alpha chain is a protein that in humans is encoded by the HLA-DMA gene. HLA-DMA belongs to the HLA class II alpha chain paralogues. HLA-DM is a heterodimer consisting of an alpha (HLA-DMA) and a beta (HLA-DMB) chain, both anchored in the membrane. It is located in intracellular vesicles. This class II molecule plays a central role in the peptide loading of MHC class II molecules by helping to release the CLIP (class II-associated invariant chain peptide) molecule from the peptide binding site. Class II molecules are expressed in antigen presenting cells (APC: B lymphocytes, dendritic cells, macrophages). The alpha chain is approximately 33-35 kDa and its gene contains 5 exons. Exon one encodes the leader peptide, exons 2 and 3 encode the two extracellular domains, exon 4 encodes the transmembrane domain and the cytoplasmic tail.
MHC Class II molecules are a class of major histocompatibility complex (MHC) molecules normally found only on professional antigen-presenting cells such as dendritic cells, macrophages, some endothelial cells, thymic epithelial cells, and B cells. These cells are important in initiating immune responses. Antigens presented by MHC class II molecules are exogenous, originating from extracellular proteins rather than cytosolic and endogenous sources like those presented by MHC class I. The loading of a MHC class II molecule occurs by phagocytosis. Extracellular proteins are endocytosed into a phagosome, which subsequently fuses with a lysosome to create a phagolysosome. Within the phagolysosome, lysosomal enzymes degrade the proteins into peptide fragments. These fragments are then loaded into the peptide-binding groove of the MHC class II molecule. Once loaded, the MHC class II-peptide complexes are transported to the plasma membrane via vesicular transport, where they present the antigens to the extracellular environment. In humans, the MHC class II protein complex is encoded by the human leukocyte antigen gene complex (HLA). Class II HLAs are composed of the classical HLA-DP, HLA-DQ, and HLA-DR and non-classical HLA-DM and HLA-DO MHC molecules. Mutations in the HLA gene complex can lead to immunodeficiency disorders such as bare lymphocyte syndrome (BLS), which is a type of MHC class II deficiency.
Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.
MORE →Brown v. Board of Education in 1954.
