Characterization of Histone-like Protein Gene Families in Fritillaria liliacea

The genome size of plants shows a thousand fold variation from the 150 Mb genome of Arabidopsis to the 140,000 Mb genome of Fritillaria. Much of this variation in genome size is due to changes in the amount of non-coding DNA. Genome complexity, in contrast to genome size, is determined in large part by the number of genes but gene number and family organization are poorly characterized in most organisms. In this study I have characterized the number and type of family members from the histone-like protein gene family in Fritillaria liliacea. The experimental approach involves exhaustive polymerase chain reaction (PCR) amplification followed by cloning. Selected clones were sequenced and phylogenetic analyses were performed to determine the relationship among family members. The histone-like gene family in Fritillaria liliacea consists of two functional genes, which may be allelic and 12 processed pseudogenes. In contrast the histone-like protein gene family in Arabidopsis consists of only one functional gene without any pseudogenes. During the course of this study, a new histone-like protein related gene family was identified. This gene family consists of 5-8 functional genes and 4 classical pseudogenes.