> How many genes does Chlamydomonas have?
> We know the DNA content, and we can approximate the average size of a
>gene..... but what's missing for the estimate of the number of genes is the
>average size of SPACES BETWEEN GENES. Restriction analysis of genomic
>fragments, where specific genes are being sought, would probably not be
>informative: who knows what other genes might lie in the intervening "blank"
>spaces? What is necessary is a sequenced region that contains the end of one
>gene and the beginning of the next. Lack of open reading frames in the
>intervening space would be a good indication that there's no gene there. If we
>had a few examples, we could get the average size of intergenic regions, and
>then estimate the total number of genes. Has anyone sequenced a long enough
>stretch of ANY region of the Chlamydomonas nuclear genome to give the size of
>an intergenic region?
> Peter Luykx
> Biology Dept.
> Univ. of Miami
>
In the course of cloning the ptx2 gene I found that the 5 kb
genomic fragment that complemented the defect detected at least 2
transcripts on northern blots. Comparing the 5'end of cDNA's
corresponding to these messages to the genomic sequence indicated
that the transcripts run in opposite directions with 134 bases
between the ends of the cDNA clones.
Greg Pazour
Worcester Foundation for Experimental Biology
