IRGSP Interim Meeting Higlights
November 22, 2003
Shanghai Institute for Biological Research
Shanghai, PRC


Sequencing Progress

The following table shows IRGSP progress in finishing BAC/PAC clones as of November 16, 2003.

Site Total PHASE1 PHASE2 PLN BAC/month
ASPGC

287

2 223 80 19
CSHL

109

3 1 105 0
Genoscope

286

1 64 220 14
KRGRP

16

9 22 0 0
NCGR

297

0 115 216 0
PGIR

40

0 6 34 22
TIGR

387

15 147 223 9
RGP

1810

41 601 1168 88
IIRGS

115

0 88 29 10
AGI

132

1 3 129 2
BRIGI

2

0 0 2 0
Total

3483
72 1270 2206 164

It is evident that at the current rate the IRGSP is on schedule to finish 1277 clones by the self imposed deadline of December, 2004.

Chromosomes 1, 4, 7, and 10 have been finished, as well as complete centromeres on chromosomes 4 and 8.


Physical Map

The summary of the current physical map, prepared by Jianzhong Wu (RGP), indicates 56 physical gaps remain. Gap size is estimated based on Fiber FISH technology, BAC finger printing, the YAC physical map, and the genetic map. About 30% of the total length of remaining gaps are in centromes.
Chr No. cM PAC/BAC clones Tile length (Mb) Gap No. Full length (Mb) Coverage (%)* Unmapped (Mb)
1 181.8 392 43.6 7 45.2 96.5 1.6
2 157.9 359 36.5 4 38.7 94.3 2.2
3 166.4 332 36.7 7 39.3 93.4 2.6
4 129.6 296 35.2 3 36.0 97.8 0.8
5 122.3 287 29.7 5 31.8 93.4 2.1
6 126.3 282 31.3 2 34.3 91.3 3.0
7 118.6 294 29.9 2 31.2 95.8 1.3
8 121.2 283 29.2 2 30.7 95.1 1.5
9 93.5 221 23.0 5 24.6 93.5 1.6
10 83.8 208 23.0 5 23.8 96.6 0.8
11 119.5 262 28.5 6 32.2 88.5 3.7
12 109.5 277 27.2 8 30.5 89.2 3.3
Total 1530.4 3493 373.8 56 398.3 93.8 24.5

*The region containing rice rDNA sequence on chromosome 9 is not included.

The estimate for total genome size of 398.3 Mb comes very close to 400.5 Mb obtained by Chen et al. (Plant Cell 14: 537, 2002).

The members have used Syngenta sequence, multiple BAC/PAC libraries, and a new 40-50 kb random sheared fosmid library, to close the gaps and extend boundaries. Thirty two gaps have been closed using these resources in the last eight months.


The members agreed to explore means to measure all remaining gaps by fiber FISH.


In another effort to close the remaining gaps, Rod Wing noted that there are 80 unanchored contigs on the AGI map covering about 12 Mb. In collaboration with the RGP, he proposes to map these contigs and to perform survey sequencing on the potentially interesting contigs to identify clones that are not on the current sequence-based map.


Sequence Quality

Members measure band size from in silico as compared with empirical digests of each finished clone with three to six enzymes. It was agreed to use two additional approaches to check sequence quality:

Cari Soderlund (AGI) has developed simulated digest software which automatically does in silico digests on finished BACs and PACs as they are posted. Clones with matching digests are automatically brought into the AGI physical map. The simulated digest software will be rewritten so that all submitted finished clones can be checked by this method.

Dick McCombie proposed, and members accepted, a mechanism that would allow CSHL and Genoscope to request trace files for five randomly chosen finished clones for each group where they will be reassembled at both sites to verify that submitted sequence meets phase 3 quality. McCombie noted that CSHL and TIGR had traded trace files for a similar exercise in the past.


Finishing Workshop

A workshop, conducted by finishers from CSHL will be held in Tsukuba, Japan on February 2-3, 2004, so that IRGSP finishers can compare notes and exchange ideas on finishing methods and how to approach problem clones.


Future Meetings

The next IRGSP meeting will be held in Tsukuba, Japan on February 4, 2004.

The next interim meeting will be held in Tucson, Arizona in conjunction with the 2nd International Symposium on Rice Functional Genomics, probably in October, 2004.

It was agreed to have monthly conference calls beginning March, 2004.


Posted by Takuji Sasaki and Ben Burr, 25 November 2003

RICE GENOME RESEARCH PROGRAM (RGP) HOME PAGE
webmaster@staff.or.jp
Copyright (C) The International Rice Genome Sequencing Project (IRGSP). 2005 All rights reserved.
RGP NIAS STAFF IRGSP