Chromosomes are the fundamental structures of genetic material in eukaryotic organisms, carrying the instructions for the development, functioning, and inheritance of genetic traits.They consist of two primary components: DNA and associated proteins. The DNA molecule contains the genetic code, whilst the proteins, predominantly histones, assist in packaging and organizing the long, linear DNA strands. The DNA within chromosomes adopts a double helix structure, with two complementary DNA strands winding around each other in a ladder-like configuration. This structure is stabilized by hydrogen bonds between complementary base pairs: adenine (A) pairs with thymine (T), and guanine (G) pairs with cytosine (C). Within the nucleus DNA is coiled around histone proteins to form nucleosomes, the fundamental repeating units of chromatin. A nucleosome consists of approximately 147 base pairs of DNA wrapped around a core of histone proteins. This packaging acts to compact the long DNA molecule, allowing it to fit within the cell nucleus. Histones themselves are small, positively charged conserved proteins that generate chromatin structure. They include histone H1, H2A, H2B, H3, and H4. Histones' positive charges interact with the negatively charged phosphate groups of DNA, promoting DNA compaction and stabilizing the nucleosome structure. Nucleosomes are connected by stretches of linker DNA, forming a higher-order structure termed the chromatin fibre. Chromosomes have specific regions called centromeres, where sister chromatids are physically held together. Centromeres are essential for proper chromosome segregation during mitosis in dividing cells. Specialized DNA sequences are also found at the ends of linear chromosomes called telomeres. They serve as protective caps, preventing the loss of genetic information during DNA replication and maintaining chromosome stability. Telomeres consist of repetitive DNA sequences that are rich in guanine (G) and cytosine (C) nucleotides. In humans, the typical telomeric repeat sequence is TTAGGG, which is repeated hundreds to thousands of times in a tandem array. At the very end of the telomere, there is a short, single-stranded DNA overhang composed of the G-rich sequence. Chromosomes often also contain within them repetitive DNA sequences, such as satellite DNA and transposable elements, that do not themselves encode genes but have structural and regulatory functions. Satellite DNA for example is often found in heterochromatic regions, which are tightly packed and transcriptionally inactive regions of the genome. In some cases, satellite DNA is also associated with the centromere, the region on a chromosome that plays a role in chromosome segregation during cell division. Centromeric satellite DNA helps in forming the kinetochore, a protein structure that attaches to microtubules during cell division, ensuring the accurate distribution of genetic material to daughter cells. Chromosomes can be visualized using various staining techniques that produce distinct banding patterns. These patterns help in identifying specific chromosomes and detecting structural abnormalities. During cell division, chromosomes condense further into highly compacted structures that are visible by light microscopy. This compaction ensures the faithful segregation of genetic material to daughter cells during mitosis and meiosis. We provide a large product catalogue of research reagents for investigating chromosome structure, including CENPA antibodies, Eg5 antibodies, SMC1 antibodies, Separase antibodies, and Rad21 antibodies. Explore our full chromosome structure product range below and discover more, for less. Alternatively, you can explore our Chromatid Cohesion and Centromere product ranges.