  We study the oscillatory behaviour of a gene regulatory network with
interlinked positive and negative feedback loop. Frequency and amplitude are
two important properties of oscillation. Studied network produces two different
modes of oscillation. In one mode (mode 1) frequency remains constant over a
wide range amplitude and in other mode (mode 2) the amplitude of oscillation
remains constant over a wide range of frequency. Our study reproduces both
features of oscillations in a single gene regulatory network and show that the
negative plus positive feedback loops in gene regulatory network offer
additional advantage. We identified the key parameters/variables responsible
for different modes of oscillation. The network is flexible in switching
between different modes by choosing appropriately the required
parameters/variables.
