The Physical Locations Of SUT And RZF Gene Families From Hevea Brasiliensis

Rubber is an important strategic material in China. Hevea brasiliensis is one of the most important sources of natural rubber, and an important economic crop for tropical and subtropical areas in China too. Sucrose is a raw material for rubber biosynthesis, and the transmenbrane transport of sucrose is mediated by sucrose transporter proteins(SUT). HbSUT genes are important genes for rubber biosynthesis, affecting the output production of natural rubber. Otherwise, Zinc finger protein is one of the most abundant regulatory factors in plant. RING zinc finger protein gene (HbRZF) maybe participate in the regulation of natural rubber biosynthesis in rubber tree. Predecessors have cloned six HbSUT genes and four C3HC4-type HbRZF genes from the rubber tree. However, these genes have not been located on chromosome. Locating the genes will reveal the linkage relations and distance between them, and other functional genes. Which effectively apply to molecular assisted breeding and comparative genomics of the rubber tree. In this study, preparing chromosome samples using the young leaves of Reyan7-33-97(2n=36). we adopted the in situ PCR (IS-PCR) and fluorescence in situ hybridization (FISH) technologies to locate HbRZF and HbSUT family genes. The main results were as follows:1.The physical locations of members of zinc finger gene family (HbRZF).HbRZFl gene was located on the long arm of chromosome6, the average percentage of the signal from centromere distance is45.76±3.18, IS-PCR signal detection rate is28.79%; HbRZF2gene was located on the long arm of chromosome3, the average percentage of the signal from centromere distance is22.25±1.02, FISH signal detection rate is12.18%; HbRZF3gene was located on the long arm of chromosome5, the average percentage of the signal from centromere distance is66.33±0.73, IS-PCR signal detection rate is36.70%; HbRZF4gene was located on the long arm of chromosome7, the average percentage of the signal from centromere distance is40.64±1.44, FISH signal detection rate is12.18%.2. The physical locations of members of sugar transporter gene family (HbSUT).HbSUTl gene was located on the long arm of chromosome1, the average percentage of the signal from centromere distance is47.45±0.50, IS-PCR signal detection rate is47.95%. HbSUT2A gene was located on the long arm of chromosome3, the average percentage of the signal from centromere distance is64.03±1.72, FISH signal detection rate is10.35%. HbSUT2B gene was located on the long arm of chromosome18, the average percentage of the signal from centromere distance is73.95±1.50, FISH signal detection rate is10.35%, and IS-PCR’s is35.6%. HbSUT3gene was located on the long arm of chromosome6, the average percentage of the signal from centromere distance is52.73±1.00, IS-PCR signal detection rate is37.5%. HbSUT4gene was located on the long arm of chromosome7, the average percentage of the signal from centromere distance is40.04±0.50, FISH signal detection rate is12.85%. HbSUT5gene was located on the long arm of chromosome15, the average percentage of the signal from centromere distance is35.25±1.50, FISH signal detection rate is12.85%, and IS-PCR’s is30.95%.3. In this study, the six HbSUTs genes were separate genes each other because of being distributed on different chromosomes. The four HbRZFs genes were also separate genes each other because of being distributed on different chromosomes. Base on the locations of other genes reported in previous literature, we gave a preliminary inference that HbSUT1and HbRT2genes were located on chromosome1long arm, so both of them were linkage genes. The four genes HbRZF2, HbSUT2A, HbREF and HbMGRl genes were located on chromosome3long arm, are linkage genes. HbRZF3and HbMybl genes were located on the long arm of chromosome5, thus they are linkage genes. HbRZFl, HbSUT3and HbRTl genes were located on the long arm of chromosome6, so they are linkage genes. HbRZF4, HbSUT4and HbPT3genes were linked because they were located on the long arm of chromosome7.