Planets excluding the nodes rule the signs. The luminaries have one sign each and the others two each.
Cancer and Leo are adjacent. Then we find Gemini and Virgo ruled by Mercury who has 'education' in his domain. The next adjacent signs are owned by Venus who is the planet of arts. Then we have Aries and Scorpio ruled by Mars, the warrior. Jupiter, who has the manthras and vedhas in his domain, rules Sagittarius and Pisces. The last two signs are owned by Saturn, the 'deliverer of justice' according to one's past 'karma'.

The Sun is the king and the Moon is the queen. Their heir is sent to Mercury, who offers him  good education; then he is entrusted to Venus from whom he learns the fine arts. Various  techniques of warfare are taught to him by Mars. Jupiter, the "guru", teaches him the "Vedas"  and mantras and prepares him for life. With the blessings of the 'Guru', he faces Saturn,   undergoes lot of sufferings and finally attains "Moksha" ( liberation ).