Growth Factors

Key Biological Properties: SCF is a growth factor that promotes the proliferation, migration, survival, and differentiation of hematopoietic progenitors, melanocytes, and germ cells . It is expressed by fibroblasts and endothelial cells throughout the body .

Expression Patterns and Tissue Distribution: SCF is expressed in various tissues, including the visceral pleura, cardia, lower lobe of the lung, pylorus, lateral nuclear group of the thalamus, middle temporal gyrus, parietal pleura, endothelial cells, skin of the hip, and seminal vesicles .

Primary Biological Functions: SCF plays a vital role in hematopoiesis (formation of blood cells), spermatogenesis (formation of sperm cells), and melanogenesis (formation of melanin) . It is essential for the survival and development of hematopoietic stem cells, melanocytes, and germ cells .

Role in Immune Responses and Pathogen Recognition: SCF is involved in the regulation of immune responses by promoting the proliferation and differentiation of immune cells . It also plays a role in pathogen recognition by enhancing the function of immune cells .

Mechanisms with Other Molecules and Cells: SCF binds to the c-KIT receptor, causing the receptor to homodimerize and auto-phosphorylate at tyrosine residues . This interaction activates multiple downstream signaling pathways, including the phosphatidylinositol-3-kinase (PI3K), Src family members, the JAK/STAT pathway, and the Ras–Raf–MAP kinase cascade .

Binding Partners and Downstream Signaling Cascades: The binding of SCF to c-KIT activates various signaling cascades that promote cell survival, proliferation, and differentiation . These pathways include the PI3K/Akt pathway, which is involved in cell survival, and the MAPK pathway, which is involved in cell proliferation .

Regulatory Mechanisms Controlling Expression and Activity: The expression and activity of SCF are regulated by various transcription factors and signaling pathways . Transcriptional regulation involves the activation of specific genes that encode SCF, while post-translational modifications, such as phosphorylation, can modulate the activity of SCF .

Transcriptional Regulation and Post-Translational Modifications: Transcription factors, such as PU.1, play a crucial role in the regulation of SCF expression . Post-translational modifications, including phosphorylation and glycosylation, can affect the stability and activity of SCF .

Biomedical Research: SCF is widely used in biomedical research to study hematopoiesis, stem cell biology, and immune responses . It is also used to culture and expand hematopoietic stem cells in vitro .

Diagnostic Tools: SCF can be used as a biomarker for certain diseases, such as mastocytosis and certain types of leukemia . Its levels can be measured to diagnose and monitor these conditions .

Therapeutic Strategies: SCF has potential therapeutic applications in regenerative medicine and stem cell therapy . It can be used to enhance the engraftment and survival of transplanted stem cells .

Role Throughout the Life Cycle: SCF plays a critical role throughout the life cycle, from development to aging and disease . During development, SCF is essential for the formation of blood cells, germ cells, and melanocytes . In adulthood, SCF continues to support the maintenance and function of these cells .

From Development to Aging and Disease: SCF is involved in various physiological processes, including tissue repair and regeneration . Dysregulation of SCF signaling can lead to various diseases, such as anemia, infertility, and pigmentation disorders .