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Prolactin is a pituitary hormone involved in the stimulation of milk production, salt and water regulation, growth, development and reproduction. The initial step in its action is the binding to a specific membrane receptor (prolactin receptor) which belongs to the superfamily of class 1 cytokine receptors. The function of the prolactin receptor is mediated, at least in part, by two families of signaling molecules: Janus kinases and signal transducers and activators of transcription. Prolactin (PRL) is a hormone involved in a variety of important functions including ion transport and osmoregulation, stimulation of milk, protein synthesis as well as the regulation of numerous reproductive functions. PRL exerts its influence on different cell types through a signal transduction pathway which begins with the binding of the hormone to a transmembrane PRL receptor. Immunoreactive PRL receptor, a member of the cytokine receptor family, varies in size (short and long forms) with tissue source and species, from ~40 kDa to 100 kDa. The PRL receptor consists of at least three separate domains: an extracellular region with 5 cysteines which contains the prolactin binding site, a single transmembrane domain and a cytoplasmic region, the length of which appears to influence ligand binding and regulate cellular function.

Proteasome 26S Subunit, Non-ATPase 13 (PSMD13) is a part of the proteasome subunit S11 family and contains one PCI domain. PSMD13 plays a role as a regulatory subunit of the 26S proteasome which takes part in the ATP-dependent degradation of ubiquitinated proteins.

RGS16 is part of the ''regulator of G protein signaling'' family. RGS16 inhibits signal transduction by increasing the GTPase activity of G protein alpha subunits thereby driving them into their inactive GDP-bound form. RGS16 Binds to G(i)-alpha and G(o)-alpha, but not to G(s)-alpha. RGS16 regulates the kinetics of signaling in the phototransduction cascade.

HMGB2 belongs to the non-histone chromosomal high-mobility group protein family which are chromatin-associated and highly spread in the nucleus of higher eukaryotic cells. HMGB2 can successfully bend DNA and form DNA circles which indicates that HMGB2 facilitates cooperative interactions between cis-acting proteins by promoting DNA flexibility. Additionally, HMGB2 takes part in the final ligation step in DNA end-joining processes of DNA double-strand breaks repair and V(D)J recombination.

OGG1 is a DNA glycosylase enzyme which takes part in base excision repair. OGG1 protein is the main enzyme accountable for the excision of 7,8-dihydro-8-oxoguanine (8-oxoG), a mutagenic base byproduct which arises as a result of exposure to reactive oxygen species (ROS). OGG1 shows beta lyase activity that nicks DNA 3'' to the lesion.

Lymphokine-activated killer T-cell-originated protein kinase (PBK) is a serine/threonine kinase related to the dual specific mitogen-activated protein kinase (MAPKK) family. PBK is abundant in placenta (is also found in the testis’ outer cell layer of seminiferous tubules) and absent from adult brain tissue. PBK is involved in the activation of lymphoid cells and supports testicular functions, with a possible role in the process of spermatogenesis. Mitotic phosphorylation is required for PBK’s catalytic activity. Once phosphorylated,PBK forms a complex with TP53, leading to TP53 destabilization and weakening of G2/M checkpoint during some kind of DNA damage. PBK is active only during mitosis. In addition, a PDZ domain in the tumor suppressor protein Dlg can coordinate with the T/SXV motif of PBK. PBK also phosphorylates MAP kinase p38, and may have a role in the activation of lymphoid cells.

PDCD6IP is a Class E VPS protein which participates in concentration and sorting of cargo proteins of the multivesicular body or incorporation into intralumenal vesicles that are generated by invagination and scission from the limiting membrane of the endosome. PDCD6IP binds to the phospholipid lysobisphosphatidic acid which is abundant in MVBs internal membranes. The MVB pathway appears to require the sequential function of ESCRT-O, -I,-II and -III complexes. PDCD6IP is an adapter for a subset of ESCRT-III proteins, such as CHMP4, to function at distinct membranes. PDCD6IP is mandatory for completion of cytokinesis. PDCD6IP takes part in HIV-1 virus budding. PDCD6IP replaces TSG101 in its function of supporting HIV-1 release. PDCD6IP takes part in the regulation of both apoptosis and cell proliferation. PDCD6IP is a cytoplasmic protein that cooperates with apoptosis-associated proteins (ALG-2 and PDCD6) and with the endocytosis-regulator CIN85. Overexpression of PDCD6IP and endophilin

Human PDE6D was initially identified as a fourth subunit of rod-specific cGMP phosphodiesterase, PDE6. PDE6D is an Oligomer composed of two catalytic chains (alpha and beta), an inhibitory chain (gamma) and the delta chain. PDE6D interacts with RPGR, ARL2 and ARL3. The catalytically active PDE6 is a heterodimer (αβ) that is controlled by two inhibitory γ subunits. Since PDE6D does not change the catalytic properties of PDEαβ, its function is still unanswered. PDE6D is expressed specifically in the retina.

PDLIM1, a cytoplasmic protein linked to the cytoskeleton, belongs to the enigma protein family. PDLIM1 holds two protein interacting domains - PDZ domain at the amino terminal end and one to three LIM domains at the carboxyl terminal. PDLIM1 enables bringing other LIM interacting proteins to the cytoskeleton. Pseudogenes related to PDLIM1 are situated on chromosomes 3, 14 and 17.

PEBP1 (Phosphatidylethanolamine binding protein 1) belongs to the phosphatidylethanolamine-binding protein family and a serine protease inhibitor that inhibits thrombin, neuropsin. PEBP1 plays a key modulatory part in several protein kinase signaling cascades. PKC phosphorylates PEBP1, resulting in the release of Raf-1 and activation of MEK and ERK. PEBP1 is expressed in many tissues and implicated in the regulation of such physiological processes as membrane biosynthesis, spermatogenesis, neural development, and metastasis suppression.
PEBP1 binds ATP, opioids and phosphatidylethanolamine, however it has lower affinity for phosphatidylinositol and phosphatidylcholine. PEBP1 may also be involved in the function of the presynaptic cholinergic neurons of the CNS. PEBP1 increases the production of choline acetyltransferase although not acetylcholinesterase. Furtheremore, PEBP1 functions in potentially sequestering toxic compounds, including locostatin which may have harmful effects on cells.
Loss of PEBP1 expression may have a significant role as prognostic marker in Gastrointestinal stromal tumors. In addition, PEBP1 is found differentially expressed in the Wernicke's Area from schizophrenia patients. PEBP1 is also, an invasion suppressor protein in nasopharyngeal carcinoma.

PEX19 is vital for peroxisome biogenesis in Saccharomyces cerevisiae. PEX19 is limited to the outer surface of peroxisomes in liver cells and is has a part in the early stage of peroxisome membrane assembly, prior to the import of matrix protein.

GPN-loop GTPase 1 (GPN1) is a member of the GPN-loop GTPase family. GPN1 is a guanosine triphosphatase enzyme which has a role in DNA repair and may function in activation of transcription. Small GTPases, which share a biochemical mechanism, act as binary molecular switches and function in the cell is nucleocytoplasmic transport of both proteins and RNA. In addition, GPN1 establishs an interface between the RNA polymerase II enzyme and chaperone/scaffolding protein, proposing that it is essential to connect RNA polymerase II to regulators of protein complex formation. GPN1 may also be involved in nuclear localization of XPA.

The proteasome is a multicatalytic proteinase complex with a highly assembled ring-shaped 20S core structure which is composed of 4 rings of 28 non-identical subunits, 2 rings are composed of 7 alpha subunits and 2 rings are composed of 7 beta subunits. Proteasomes are found throughout eukaryotic cells at a high concentration and cleave peptides in an ATP/ubiquitin-dependent process in a non-lysosomal pathway. PSMA7 is part of the peptidase T1A family, that is a 20S core alpha subunit. PSMA7 interacts particularly with the hepatitis B virus X protein, a protein critical to viral replication. PSMA7 is involved in regulating hepatitis virus C internal ribosome entry site activity that is crucial for viral replication. PSMA7 is in charge for regulating the hypoxia-inducible factor-1alpha, a transcription factor important for cellular responses to oxygen tension. PSMA7 is characterized by its ability to cleave peptides with Arg, Phe, Tyr, Leu, and Glu adjacent to the leaving group at neutral or slightly basic pH. PSMA7 interacts specifically with two subdomains of HIF-1alpha and inhibited the transactivation function of HIF-1alpha under both normoxic and hypoxia-mimicking conditions.

PSMD9 is a multicatalytic proteinase complex with a highly ordered structure composed of 2 complexes, a 20S core and a 19S regulator. PSMD9 acts as a chaperone through the assembly of the 26S proteasome, specifically of the base subcomplex of the PA700/19S regulatory complex (RC). During the base subcomplex compilation, PSMD9 is part of an intermediate PSMD9:PSMC6:PSMC3 module, also called modulator trimer complex. PSMD9 is released during the further base assembly process.

Matrix metalloproteinase-14 (MMP14), is a membrane-anchored zinc-binding endopeptidase which is expressed at the leading edge of different invasive carcinomas and also promotes tumor cell invasion through degradation of the extracellular matrix. MMP14 takes a vital part in extracellular matrix, ECM, remodeling by having the capability to degrade type I collagen, activate pro-MMP-2 and process cell adhesion molecules for instance CD44 and integrin alpha V. MMP14 is a key enzyme in many physiological as well as pathological processes for example angiogenesis & tumor invasion.

PBX/Knotted 1 Homeobox 1 (PKNOX1) is a DNA-binding factor which takes part in the regulation of the transcriptional activity of AP-1 containing promoters. PKNOX1, which is also known as UEF3, PRP-1 and p64, is a Hmeobox protein. PKNOX1 forms stable complexes containing PBX proteins which synergize with AP-1 binding factors.

NANOGP8 belongs to the homeobox family of DNA binding transcription factors which is known to conserve pluripotency of embryonic stem cells. One change only separate NANOGP8 from NANOG – instead of 'Gln-253' in the inferred amino acid sequence in NANOG there is a ‘His-253’ in NANOGP8.

Biglycan (BGN) is a small cellular or pericellular matrix proteoglycan which takes part in assembly of collagen fibrils and muscle regeneration. BGN is closely correlated in structure to two other small proteoglycans, decorin and fibromodulin. BGN interacts with several proteins involved in muscular dystrophy, including alpha-dystroglycan, alpha- and gamma-sarcoglycan and collagen VI. BGN is also critical for the assembly of the dystrophin-associated protein complex.

Phosducin-like protein (PDCL) is a member of the phosducin family. PDCL is a putative modulator of heterotrimeric G proteins. PDCL shares broad amino acid sequence homology with phosducin, a phosphoprotein expressed in the retina and pineal gland. Both PDCL and phosphoducin regulate G-protein signaling by binding to the beta-gamma subunits of G proteins.

The recombinant Protein A/G is a genetically engineered protein comprised of 7 IgG-binding domains EDABC-C1C3, corresponding to the Protein A and G domains which are included in the recombinant sequence. The Protein A part is from Staphylococcus aureus segments E, D, A, B and C. The Protein G part is from Streptococcus segments C1 and C3. The recombinant Protein A/G has a broader binding capacity than either Protein A or Protein G alone. The recombinant Protein A/G is ideal for purification of monoclonal or polyclonal IgG antibodies. Protein A/G binds to various human, mouse and rat IgG subclasses such as the human IgG1, IgG2, IgG3, IgG4; mouse IgG2a, IgG2b, IgG3 and rat IgG2a, IgG2c. In addition, Protein A/G binds to total IgG from cow, goat, sheep, horse, rabbit, guinea pig, pig, dog and cat.

BPGM is found at high concentrations in red blood cells where it binds to and decreases the oxygen affinity of hemoglobin. PGM deficiency increases the oxygen affinity of cells. BPGM is a multifunctional enzyme that catalyzes 2,3-DPG synthesis through its synthetase activity, and 2,3-DPG degradation using its phosphatase activity. BPGM has phosphoglycerate phosphomutase activity. Mutations in BPGM cause hemolytic anemia. BPGM catalyzes the reaction of EC 5.4.2.1 (mutase) and EC 3.1.3.13 (phosphatase), but with a reduced activity.

PDGF-AA, PDGF-BB and PDGF-AB, are potent mitogens for a variety of cell types including smooth muscle cells, connective tissue cells, bone and cartilage cells, and some blood cells. The PDGF is stored in platelet alpha-granules and released upon platelet activation. The PDGF is involved in a number of biological processes, including hyperplasia, chemotaxis, embryonic neuron development, and respiratory tubule epithelial cell development. Two distinct signaling receptors used by PDGF have been identified and named PDGFR-alpha and PDGFR-beta. PDGFR-alpha is high-affinity receptor for each of the three PDGF forms. On the other hand, PDGFR-beta interacts with only PDGF-BB and PDGF-AB.