Saute ginger and garlic in hot sesame oil in a small saucepan over medium-high heat for 2 minutes. Stir in wine and next 3 ingredients. Remove from heat, and stir in tahini. Keep tahini sauce warm.
Cut tuna into 20 (1-inch) pieces. Thread tuna and artichokes alternately onto 6-inch skewers.
Grill, covered with grill lid, over high heat (400° to 500°) about 3 minutes, turning and basting with tahini sauce. Serve with Spinach Rice. Garnish, if desired.