Biochemical Systematics of Gymnosperms (2), Seed Protein Peptides of Pinaceae

Hu Zhi-Ang, Liu Zhang-Jiang, Wang Hong-Xin

Received:1900-01-01 Revised:1900-01-01 Online:1984-10-18 Published:1984-10-18
Contact: Hu Zhi-Ang

Abstract:

By means of SDS linear gradient polyacrylamide gel electrophoresis, seed

protein peptides of 50 species belonging to 10 genera of Pinaceae were analysed. A

major peptide possessing molecular weight about 45000 daltons is shared by every species

in Pinaceae. There are many peptides of higher molecular weight in seeds, but their

content is very low. In order to make a series of quantitative comparisons between any

two taxa, we define “peptide distance” as follows:

number of different peptides between 2 taxa

peptide distance= ------------

total number of peptides in 2 taxa

In the following table, the peptide distances of some genera are shown together with

other molecular data about Pinaceae.

genus	ancientry of genus	antigen distance	zymogram distance	peptide distance
Larix	Miocene to now (25My)	0	0	0.08
Cedrux Pseudotsuga Keteleeria	Oligocene to now (35My)	_ _ _	0 0.17 0.29	_ _ _
Tsuga Abies	Eocene to now (57My)	1.0 _	_ 0.44	_ 0.35
Picea	Late Cretaceous-(67-100 My)	0.5	0.30	0.18
Pinus	Early Cretaceous-(100-130My)	2.3	0.67	0.39

From the data cited above, there are positive correlation between molecular data

and the ancientry of genera in Pinaceae. Therefore, the rate of molecular evolution

seems stable. Based on the data of peptide distances, it is suggested that the variation be

discontinuous between the genera, but continuous within a genus. A comparison between

molecular and morphological evolution indicates that the two evolutions are different not only in rate but in mechanism as well.

Key words: Pinaceae, seed protein peptides, molecular evolution

Hu Zhi-Ang, Liu Zhang-Jiang, Wang Hong-Xin. Biochemical Systematics of Gymnosperms (2), Seed Protein Peptides of Pinaceae[J]. .

[1]	Wang Xiao-quan, Han Ying, Deng Zheng-rong, Hong De-yuan. Phylogeny of the Pinaceae Evidenced By Molecular Biology [J]. , 1997, 35(2): 97-106.
[2]	Li Lin-chu. Studies on the Karyotype and Systematic Position of Larix Mill. (Pinaceae) [J]. , 1993, 31(5): 405-412.
[3]	Ying Tsun-Shen. Areography of the Gymnosperms of China (1) Distribution of the Pinaceae of China [J]. , 1989, 27(1): 27-38.
[4]	Hu Zhi-Ang, Wang Hong-Xin, Liu Chang-Jiang, Qian Zhong-Xing. Biochemical Systematics of Gymnosperms (3)—On the Systematic Position of Tax aceae from Their Seed Protein Peptides and Needle Peroxidases [J]. , 1986, 24(4): 260-263.
[5]	Li Xia-Bing. Studies on the Constituents and Distribution of Fatty Acids in Seed Oils from Pinaceae of China [J]. , 1985, 23(4): 259-263.

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