The Lotus japonicus Genome

japonicus,which encode for the aforementioned
enzymes, their nomenclature, and the codes
available for them in Kazusa 2.5 database as well
as the corresponding ortholog genes inA. thali-
ana. We also comparatively analyze the levels of
expression determined by qRT-PCR that we have
obtained for all of these genes in leaves, roots,
and nodules ofL. japonicusplants growing under
N-sufficient conditions. All these results are also
summarized in Table11.1.

11.2 Enzymes Involved in

Ammonium Assimilation

11.2.1 The GS-GOGAT Cycle

Glutamine is thefirst organonitrogen compound

that is synthesized in the plants as a result of both

primary and secondary ammonium assimilation,

by means of the glutamine synthetase (GS)/glu-

tamate synthase (GOGAT) cycle. Glutamine

Table 11.1 Genes for ammonium assimilation inL. japonicus

Gene name Code in Kazusa 2.5 Levels of expression Ortholog genes inA. thaliana

Leaves Roots Nodules

LjGln1.1 chr2.CM0312.1480.r2.m HHHAt5g37600(AtGln1.1)

At1g66200(AtGln1.2)

At3g17820(AtGln1.3)

At5g16570(AtGln1.4)

At1g48470(AtGln1.5)

LjGln1.2 chr6.CM0014.300.r2.m VH VH VH

LjGln1.3 LjSGA_030247.1 LVLVL

LjGln1.4 LjSGA_058827.1 LNDND

LjGln1.5 LjSGA_019428.1 VL ND ND

LjGln2 chr6.CM0139.890.r2.m VH VH VH At5g35630(AtGln2)

LjGlu1 chr1.CM0009.170.r2.d VH H H At5g04140(AtGlu1)

At2g41220(At Glu2)

LjGlt1 LjSGA_035611.1 VL L L At5g53460(AtGlt1)

LjGlt2 LjSGA_037992.1 HHH

LjGdh1 chr1.CM0104.2530.r2.m HVHLAt5g18170(AtGdh1)

At5g07440(AtGdh2)

At3g03910(AtGdh3)

LjGdh2 chr4.CM2142.210.r2.a VL L VL

LjGdh3 chr2.CM0021.1320.r2.m ND VL ND

LjGdh4 chr3.CM1488.210.r2.d

chr3.CM1488.260.r2.d

chr3.CM1488.250.r2.d

chr3.CM1488.230.r2.d

HHHAt1g51720(AtGdh4)

LjAsn1 chr5.CM0071.330.r2.d VH VH H At3g47340(AtAsn1)

At5g65010(AtAsn2)

At5g10240(AtAsn3)

LjAsn2 LjT47C13.80.r2.d VL VH VH

LjAsn3 LjT09J04.190.r2.d LLL

LjNse1 chr5.CM0096.20.r2.m VH H L At3g16150(AtAspGB1)

LjNse2 chr4.CM0087.1740.r2.m LHHAt5g08100(AtAspGA1)

LjNse3 LjSGA_021574.1 HLVLAt3g16150(AtAspGB1)

Level of expression (relative units) Level of expression Symbol

0 – 0.001 Undetectable ND

0.001–0.01 Very low VL

0.01–0.1 Low L

0.1– 1 High H

1 – 10 Very high VH

118 C.M. Pe ́rez-Delgado et al.