Figure 3. ss regulatory regions upregulate and downregulate expression frequency through interchromosomal communication.

A. Wild type ss locus over deficiency1.

B. transgene4 upregulates expression frequency from the endogenous ss gene in cis.

C. Quantification of A, B, and D

D. transgene4 upregulates expression frequency from the endogenous ss gene in trans.

E. transgene4 upregulates expression, though less efficiently, from the ss locus on the non-homologous 2^nd chromosome.

F. Quantification of E.

G. Ss/Rh4 is not expressed in ss^{low freq1} hemizygous mutants.

H. The normal regulatory regions of the ss^{prot null1} allele upregulate Ss/Rh4 expression from the ss^{low freq1} allele.

I. Wild type ss homozygous loci.

J. The regulatory regions of the ss^{low freq1} allele downregulate Ss/Rh4 expression from the wild type ss allele.

K. Quantification of G–J.