Cai Z H, Li P, Dong T T, Tsim K W
Department of Biology and Biotechnology Research Institute, Hong Kong University of Science and Technology, China.
Planta Med. 1999 May;65(4):360-4. doi: 10.1055/s-1999-14003.
Beimu (bulbs of Fritillaria) is an important traditional Chinese herbal medicine commonly used as an antitussive and expectorant. There are about 25 species and varieties of Fritillaria that carry the name Beimu on commercial markets. The price for each Beimu may differ by more than 100-fold. However, the identification of the origin of a particular species on the market is difficult. Here, a molecular method was used to identify various species of Fritillaria regardless of their geographical origin. The 5S-rRNA coding sequence is highly conserved in higher eukaryotes, but the spacer sequence of the 5S-rRNA gene is variable among different species. Total genomic DNA from fresh leaves and bulbs of Fritillaria cirrhosa, F. puqiensis, F. anhuiensis, and F. thunbergii was extracted. The 5S-rRNA spacer region of the extracted DNAs was amplified by PCR with a pair of primers located within the conserved coding region. The isolated cDNA clones (approximately 600 bp) covering the 5S-rRNA spacer domain were sequenced. By aligning the isolated nucleotide sequences of the four Fritillaria species, sequence diversity was found in the spacer region. Furthermore, a unique EcoR I site was used for the rapid identification of different species of Fritillaria. To our knowledge, this is the first report on the detection of 5S-rRNA spacer domain sequences of Fritillaria and their use to identify species.
贝母（川贝母）是一种重要的传统中药材，常用作镇咳祛痰药。在商业市场上，约有25种贝母属植物被称为贝母。每种贝母的价格差异可能超过100倍。然而，市场上特定品种的产地鉴定却很困难。在此，采用一种分子方法来鉴定不同种类的贝母，无论其地理来源如何。5S - rRNA编码序列在高等真核生物中高度保守，但5S - rRNA基因的间隔序列在不同物种间存在差异。提取了川贝母、蒲圻贝母、安徽贝母和浙贝母新鲜叶片和鳞茎的总基因组DNA。用位于保守编码区内的一对引物通过PCR扩增提取DNA的5S - rRNA间隔区。对分离得到的覆盖5S - rRNA间隔结构域的cDNA克隆（约600 bp）进行测序。通过比对四种贝母属植物分离得到的核苷酸序列，发现间隔区存在序列多样性。此外，利用一个独特的EcoR I酶切位点对不同种类的贝母进行快速鉴定。据我们所知，这是关于贝母5S - rRNA间隔结构域序列检测及其用于物种鉴定的首次报道。
