Table 4: Site-specific frequencies and position weight matrix (PWM) for 301 3′ ss. The consensus sequence (UUUUUUUUAYAG ∣GCUUC) can be obtained from those large site-specific PWM entries, with the most important sites in bold italics . The χ 2 test is performed for each site against the expected background frequencies. The sites are labeled with first-exon site as 1. The PWM is nearly identical when the introns in 5′ UTR were excluded.

SiteACGUχ 2 𝑃 ACGU

−1270583713651.7290.0000001−0.48980.0122−0.72640.7114
−1179512314879.5110.0000001−0.3161−0.1727−1.40740.8332
−10864514156105.1310.0000001−0.1941−0.3525−2.11550.9090
−9433323202236.0630.0000001−1.1886−0.7978−1.40741.2812
−8564331171130.2160.0000001−0.8100−0.4178−0.98011.0412
−7102353113354.2560.00000010.0512−0.7134−0.98010.6793
−6103463811423.1300.00003800.0653−0.3210−0.68810.4574
−5100362514068.9250.00000000.0228−0.6729−1.28820.7532
−414527418845.4730.00000010.5574−1.0854−0.57900.0850
−3151270159284.8240.0000002−2.68771.1404−8.23500.9364
−2299110605.7890.00000031.5998−5.5977−5.6756−8.2346
−10030101171.4430.0000004−8.2345−8.23512.2908−8.2346
11093974799.9360.01912080.1467−0.55800.2697−0.0701
2846655966.0360.1098600−0.22790.1981−0.15710.2102
31035850902.9690.39648770.06530.0122−0.29400.1173
49645561048.6550.0342400−0.0359−0.3525−0.13120.3253
510069399311.6980.00849380.02280.2620−0.65080.1645