@article {10224,
	title = {Specific role of LeMAN2 in the control of seed germination exposed by overexpression of the LeMAN3 gene in tomato plants},
	journal = {PLANTA},
	volume = {227},
	number = {1},
	year = {2007},
	pages = {199-209},
	abstract = {Endo-beta-mannanase is one\&nbsp;of\&nbsp;the\&nbsp;key enzymes involved\&nbsp;in\&nbsp;the\&nbsp;hydrolysis\&nbsp;of\&nbsp;the\&nbsp;mannan-rich cell walls\&nbsp;oftomato\&nbsp;(Solanum lycopersicon) seeds. Two isoforms\&nbsp;of\&nbsp;endo-beta-mannanase have been characterized\&nbsp;intomato\&nbsp;seeds:\&nbsp;LeMAN2\&nbsp;is active\&nbsp;in\&nbsp;the\&nbsp;micropylar area prior to\&nbsp;germination\&nbsp;and LeMAN1 is active aftergermination\&nbsp;in\&nbsp;all endosperm cells surrounding\&nbsp;the\&nbsp;cotyledons. To explore whether general mannanase activity\&nbsp;in\&nbsp;the\&nbsp;endosperm cap is sufficient to promote\&nbsp;germination,\&nbsp;the\&nbsp;gene\&nbsp;encoding Le.MAN3 was inserted into transgenic\&nbsp;tomato\&nbsp;plants\&nbsp;under\&nbsp;the\&nbsp;control\&nbsp;of\&nbsp;a CaMV-35S promoter. Expression\&nbsp;of\&nbsp;LeMAN3\&nbsp;was evident\&nbsp;in\&nbsp;the\&nbsp;endosperm cap and\&nbsp;in\&nbsp;the\&nbsp;lateral endosperm\&nbsp;of\&nbsp;the\&nbsp;transgenic seeds 10 min after imbibition. An activity test indicated increased activity\&nbsp;of\&nbsp;endo-beta-mannanase\&nbsp;in\&nbsp;the\&nbsp;transgenic lines relative to\&nbsp;thecontrol\&nbsp;line\&nbsp;in\&nbsp;all\&nbsp;seed\&nbsp;parts, during\&nbsp;the\&nbsp;first 20 h\&nbsp;of\&nbsp;imbibition. However,\&nbsp;overexpression\&nbsp;of\&nbsp;LeMAN3\&nbsp;intransgenic seeds inhibited\&nbsp;seed\&nbsp;germination\&nbsp;at both optimal and suboptimal temperatures. Detailed RT-PCR analyses revealed\&nbsp;the\&nbsp;transcription patterns\&nbsp;of\&nbsp;the\&nbsp;genes encoding\&nbsp;the\&nbsp;various mannanase isoforms, and indicated a delay\&nbsp;in\&nbsp;LeMAN2\&nbsp;transcription\&nbsp;in\&nbsp;the\&nbsp;endosperm cap\&nbsp;of\&nbsp;the\&nbsp;transgenic seeds. Interestingly, tissue-print assays indicated similar mannanase activity\&nbsp;in\&nbsp;the\&nbsp;micropylar areas for both transgenic andcontrol\&nbsp;seeds. These results indicate that\&nbsp;overexpression\&nbsp;of\&nbsp;active endo-beta-mannanase\&nbsp;in\&nbsp;the\&nbsp;endosperm cap is not sufficient to enable hydrolysis\&nbsp;of\&nbsp;the\&nbsp;cell walls or to promote\&nbsp;germination\&nbsp;of\&nbsp;tomato\&nbsp;seeds. Cell-wall hydrolysis\&nbsp;in\&nbsp;these endosperm cells is under tight\&nbsp;control\&nbsp;and requires\&nbsp;the\&nbsp;specific\&nbsp;activity\&nbsp;of\&nbsp;LeMAN2.},
	url = {http://link.springer.com/article/10.1007\%2Fs00425-007-0607-y},
	author = {Belotserkovsky, Harel and Berger, Yael and Ron Shahar and Wolf, Slunuel}
}
