H3F3B（H3 histone， family 3B (H3.3B)），癌症关联基因，基因ID：3021，组蛋白是负责真核生物染色体纤维核小体结构的基本核蛋白。四个核心组蛋白（h2a、h2b、h3和h4）中的两个分子形成一个八聚体，大约146bp的DNA被包裹在一个称为核小体的重复单元中。连接组蛋白h1与核小体之间的连接DNA相互作用，并在染色质压缩成高阶结构的过程中发挥作用。这个基因包含内含子，它的mRNA是多聚腺苷酸化的，不像大多数组蛋白基因。该基因编码的蛋白是一个复制无关的组蛋白，属于组蛋白H3家族。该基因的假基因已在X染色体、5号、13号和17号染色体上鉴定出来。Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of the four core histones (H2A， H2B， H3， and H4) form an octamer， around which approximately 146 bp of DNA is wrapped in repeating units， called nucleosomes. The linker histone， H1， interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures. This gene contains introns and its mRNA is polyadenylated， unlike most histone genes. The protein encoded by this gene is a replication-independent histone that is a member of the histone H3 family. Pseudogen。