Rubber composition and tire

A pneumatic tire comprising:

• at least one of a base tread, a cushion, and a tie gum that are prepared using a rubber composition comprising:
• a rubber component which contains
• (a) 10 to 30% by mass in 100% by mass of the rubber component of at least one of a butadiene rubber modified by a compound represented by the formula (1):
• wherein R1, R2 and R3 are the same or different and independently represent an alkyl group, an alkoxy group, a silyloxy group, an acetal group, a carboxyl group, a mercapto group, or a derivative thereof;
• R4 and R5 are the same or different and independently represent a hydrogen atom or an alkyl group;
• and n represents an integer, and
• a tin-modified polybutadiene rubber resulting from polymerization with a lithium initiator and having a tin atom content of 50 to 3000 ppm, a vinyl-bond content of 5 to 50% by mass, and a molecular weight distribution (Mw/Mn) of 2 or less;
• (b) 10 to 40% by mass of a modified styrene-butadiene rubber having a bound-styrene content of 21% by mass or less;
• and
• (c) 20 to 80% by mass of a diene rubber other than (a) and (b);
• (d) 7 to 50 parts by mass of silica per 100 parts by mass of the rubber component;
• and
• (e) 5 to 50 parts by mass of carbon black per 100 parts by mass of the rubber component, said carbon black having a nitrogen adsorption specific surface area of 20 to 50 m2/g.