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Small Ubiquitin-like Modifiers (SUMOs) are a family of small, related proteins that can be enzymatically attached to a target protein by a post-translational modification process termed sumoylation. Unlike ubiquitination, which targets proteins for degradation, sumoylation participates in a number of cellular processes, such as nuclear transport, transcriptional regulation, apoptosis, and protein stability. All SUMO proteins share the conserved ubiquitin domain and the C-terminal diglycine cleavage/attachment site. Human SUMO2, also known as Sentrin2 and SMT3B is synthesized as a 95 amino acid (aa), 11 kDa propeptide that contains a two aa C-terminal prosegment, and an 18 aa N-terminal protein interacting region (aa 33 -50). Following prosegment cleavage, the C-terminal glycine is enzymatically attached to a lysine on a target protein. Human SUMO2 shares 100% sequence identity to SUMO-2 from mouse. SUMO2 also has very high sequence homology to SUMO3 and SUMO4, 86 % and 85%, respectively. SUMO2 shares only 44% sequence identity to SUMO1.

MAPRE1 (EB1) is a member of the intermediate/early gene family. MAPRE1 was first identified by its binding to the APC protein, which is often mutated in familial and sporadic, forms of colorectal cancer. MAPRE1 localizes to microtubules, especially the growing ends, in interphase cells. During mitosis, MAPRE1 is associated with the centrosomes and spindle microtubules. MAPRE1 is involved in microtubule polymerization, and spindle function by stabilizing microtubules and anchoring them at centrosomes.

HSPB8 is part of the superfamily of small heat-shock proteins containing a conservative alpha-crystallin domain at the C-terminal part of the molecule. HSPB8 is induced by estrogen in estrogen receptor-positive breast cancer cells. HSPB8 protein functions as a chaperone in association with BAG3, a stimulator of macroautophagy. HSPB8 participates in the regulation of cell proliferation, apoptosis, and carcinogenesis. Mutations in HSPB8 gene have been related with different neuromuscular diseases, including Charcot-Marie-Tooth disease.

Alpha crystallins are composed of two gene products ; alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein(sHSP also known as the HSP20). They act as molecular chaperones and hold them in large soluble aggregates. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional function of a-crystallins are an autokinase activity and participation in the intracellular architecture. The expression of alpha-A is preferentially restricted to the lens cell.

TCL1A (T-cell leukemia/lymphoma 1A) is a protein with a possible role in intracellular regulation of T cell signaling. TCL1A enhances cell proliferation, stabilizes mitochondrial membrane potential and promotes cell survival. TCL1A is restricted in the T-cell lineage to immature thymocytes and activated peripheral lymphocytes. TCL1A is preferentially expressed early in T and B-lymphocyte differentiation. Chromosomal anomalies activating TCL1A are found in chronic T-cell leukemias (T-CLL).
TCL1A enhances the phosphorylation and activation of AKT1, AKT2 and AKT3. TCL1A promotes nuclear translocation of AKT1. TCL1A binds to the pleckstrin homology domain of Akt (protein kinase B) family proteins, which facilitates Akt dimerization and activity. By increasing Akt activity, TCL1A can enhance the serine/threonine phosphorylation of major Akt signaling substrates, for example Ikk complex, mTOR, BAD, p70S6 kinase, FOXO transcription factors and GSK3b. These substrates regulate cellular differentiation, growth, survival, and metabolism.

GroES protein is the co-chaperonin of GroES in E.coli and assists protein folding. GroEL mediated folding requires the co-chaperonin GroES which is essential for viability. GroES is composed of a single heptameric ring of 10kDa subunits that binds to the ends of the GroEL cylinder. GroES gene was amplified by PCR from E.coli and cloned into an expression vector. This protein was overexpressed in E.coli and was purified by using conventional chromatography techniques.

CCL4L1 (C-C motif chemokine 4-like) is a member of to intercrine beta (chemokine CC) family. The CCL4L1 protein is similar to CCL4 which inhibits HIV replication in peripheral blood monocytes which express CCR5.

Microtubule-associated protein tau (MAPT or Tau) is a protein that stabilizes microtubules. MAPT is abundant in neurons in the central nervous system and is less common elsewhere. When MAPT is defective, and no longer stabilizes microtubules properly, it can result in dementias, such as Alzheimer's disease.

Troponin I (TnI), troponin T (TnT) and troponin C (TnC) form the troponin complex of the thin filaments of striated muscle. TnI is acts as the inhibitory subunit by blocking actin-myosin interactions and thereby mediating striated muscle relaxation. The TnI subfamily contains 3 genes: TnI-skeletal-fast-twitch, TnI-skeletal-slow-twitch, and TnI-cardiac. The TNNI3 gene encodes the TnI-cardiac protein and is exclusively expressed in cardiac muscle tissues. Mutations in the TNNI3 gene cause familial hypertrophic cardiomyopathy type 7 (CMH7) and familial restrictive cardiomyopathy (RCM).

STMN1 takes part in the regulation of the microtubule filament structure by destabilizing microtubules. STMN1 promotes the disassembly of microtubules and prevents assembly. STMN1 is a ubiquitous cytosolic phosphoprotein which functions as an intracellular relay integrating regulatory signals of the cellular environment. Stathmin functions as an Oncoprotein in regulation of the cell cycle. Stathmin mutation results in uncontrolled cell proliferation. Stathmin expression associates with cervical carcinogenesis and tumor progression, thus Stathmin is an important prognostic marker in cervical carcinoma. STMN1, takes part in the prevenative progression of ER-positive primary in breast cancer. Somatic mutation in STMN1 effects cell homeostasis that leads to tumorigenicity.

BIN2, also known as Bridging Integrator 2, is a cytoplasmic protein. BIN2 comprises one BAR domain and Interacts with BIN1. BIN2 is highly expressed in some hematopoietic tissues, including peripheral blood, colon, thymus and placenta. BIN2 stimulates cell motility and migration, most likely through its interaction with the cell membrane and with podosome proteins which mediate interaction with the cytoskeleton and likewise modulates membrane curvature & mediates membrane tubulation.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

Human immunodeficiency virus (HIV) is a retrovirusthat can lead to a condition in which the immune systembegins to fail, leading to opportunistic infections. HIV primarily infects vital cells in the humanimmune systemsuch as helper T cells(specifically CD4+ T cells), macrophagesand dendritic cells. HIV infection leads to low levels of CD4+ T cells through three main mechanisms: firstly, direct viral killing of infected cells; secondly, increased rates of apoptosisin infected cells; and thirdly, killing of infected CD4+ T cells by CD8 cytotoxic lymphocytesthat recognize infected cells. When CD4+ T cell numbers decline below a critical level, cell-mediated immunityis lost, and the body becomes progressively more susceptible to opportunistic infections. HIV was classified as a member of the genus Lentivirus, part of the family of Retroviridae. Lentiviruses have many common morphologies and biological properties. Many species are infected by lentiviruses, which are characteristically responsible for long-duration illnesses with a long incubation period. Lentiviruses are transmitted as single-stranded, positive-sense, enveloped RNA viruses. Upon entry of the target cell, the viral RNA genomeis converted to double-stranded DNAby a virally encoded reverse transcriptasethat is present in the virus particle. This viral DNA is then integrated into the cellular DNA by a virally encoded integraseso that the genome can be transcribed. Once the virus has infected the cell, two pathways are possible: either the virus becomes latentand the infected cell continues to function, or the virus becomes active and replicates, and a large number of virus particles are liberated that can then infect other cells.

Hsp70-binding protein 1 (HSPBP1) is a member of a family of eukaryotic proteins identified as nucleotide exchange factors for HSP 70 that exhibit varying degrees of compartment and species specificity. HSPBP1 is localized mainly in cytoplasm and nucleus but is also found extracellularly. HSPBP1 is mostly expressed in heart and skeletal muscle .HSPBP1 binds to HSP 70, inhibits its activity and promotes dissociation of nucleotides from the HSP 70 ATPase domain. In addition, HSPBP1 inhibits HSPA1A chaperone activity by changing the conformation of the ATP-binding domain of HSPA1A and obstructing the ATP binding. HSPBP1 may also have a role in tumor (dys)regulation of chaperone proteins. Furthermore, HSPBP1 hinders ubiquitination mediated by STUB1 and inhibits chaperone-assisted degradation of immature CFTR.

Transferrin is the iron-transport protein of vertebrate serum and donates iron to cells through interaction with a specific membrane receptor, CD71. Transferrin appears to be indispensable for most cells growing in tissue culture.
It is referred to frequently as a growth factor because, in analogy to other growth factor-receptor interactions, proliferating cells express high numbers of transferrin receptors, and the binding of transferrin to their receptors is needed for cells to initiate and maintain their DNA synthesis. Apart from its role as an iron transport protein transferrin acts as a cytokine and has functions that may not be related to its iron-carrying capacity.

Hemopexin (or haemopexin) is a plasma protein that binds heme with the highest affinity of any known protein. Hemopexin is generally expressed in liver, and belongs to acute phase reactants, the synthesis of which is induced after inflammation. Heme is potentially very toxic because of its ability to intercalate into lipid membrane and to generate hydroxyl radicals. Hemopexin’s function of scavenging the heme released or lost by the turnover of heme proteins such as hemoglobin defends the body from the oxidative damage that free heme can cause. Additionally, hemopexin discharges its bound ligand for internalisation upon interacting with a specific receptor located on the surface of liver cells. This hemopexin function is in order to preserve the body's iron. Hemopexin’s levels in the serum are an indication of how much heme is present in the blood. Low Hemopexin levels show that there is a lot of it in the serum. For that reason, low hemopexin levels indicate that there has been consid

Hepatoma-derived growth factor, related protein 3 (HDGFRP3/HDGF2) is the original member of a family of polypeptides labeled HDGF related proteins (HRPs). The HDGF2 protein augments DNA synthesis and may play a part in cell proliferation. HDGF2 is expressed primarily in the testis and the brain, to an intermediate extent in the heart, and to a slight extent in the ovaries, kidneys, spleen, and liver in humans.

Histone is vastly alkaline protein exists in eukaryotic cell nuclei which set and direct the DNA into structural units named nucleosomes. 5 key families of histones are: H1/H5, H2A, H2B, H3, including H4. The core histones are H2A, H2B, H3 and H4, whereas histones H1/H5 are identified as the linker histones. Moreover the dynamics of chromatin structure depend on posttranslational modification of histones in addition to the appearance of different histone variants. Histone H3 as well as H4 are modified covalently at several residues. The histone code is constitute by these and the H2A/H2B modifications.

SEPT2 is a GTPase which is mandatory for cytokinesis and related to exocytosis. Septin-2 protein is able to hetero-oligomerize with Septin6, 7 and in addition takes part in the organization of new growth in organisms. SEPT2 is associated with a Tau-based paired helical filament core and contributes to the creation of neurofibrillary tangle as integral constituents of paired helical filaments.

SDCBP2 has two class II PDZ domains. PDZ domains assist protein-protein interactions by attaching to the cytoplasmic C-terminus of transmembrane proteins, and PDZ-containing proteins mediate cell signaling and the organization of protein complexes. SDCBP2 attaches to phosphatidylinositol 4, 5-bisphosphate (PIP2) and take part in nuclear PIP2 arrangement and cell division.

Type IV collagen is a major structural component of basement membranes. It is a multimeric protein composed of 3 alpha subunits, which are encoded by 6 different genes, alpha 1 through alpha 6. Each of these alpha subunits can form a triple helix structure with 2 other subunits to form type IV collagen. The Goodpasture syndrome is a condition in which autoantibodies bind to the collagen molecules in the basement membranes of alveoli and glomeruli. The epitopes that elicit these autoantibodies are restricted basically to the non-collagenous C-terminal domain of the protein. There are numerous alternative transcripts that appear to be unique to the human COL4A3 and alternative splicing is limited to the six exons that encode this C-terminal domain. COL4A3 is also linked to an autosomal recessive form of Alport syndrome. The mutations contributing to the Alport syndrome are also situated within the exons that encode this C-terminal region. COL4A3 is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. Several exons of COL4A3 are interspersed with exons of an uncharacterized gene which is on the opposite strand.